Inside Mining April 2016 by 3S Media

www.miningne.ws

af r ic an u pdates on th e

g ro un d a n d un d e rg ro un d

DRDGOLD

The era of aggressive returns

tARKWA GOLD Mine

BANIO project

custom screens

Excellence breeds success

Licence to mine

The African quandary

ISSN 1999-8872 • R50.00 (incl. VAT) • Vol. 09 • No. 04 • April 2016

contents

afr ic an up dates on the g round a nd underg round

Quality samples equal quality results 12

Taking better ore samples will produce better-quality results, especially where thousands of tonnes of ore needs to be represented by miniscule ore sample sizes.

APRIL

32 Editor’s Comment

Minerals Processing

An evolving science

Saving on every level

Cover Story

Underground development

The era of aggressive returns

Africa Round-up 6

News from around the continent

Economics, Finance & Risk 8

SA vs the world

Focus on Africa: Gabon 10

Licence to mine

www.miningne.ws

Turnkey solutions for Africa

Unbreakable bonds

Hydrometallurgy Assessing gold particle floatability

Commodity: Gold & PGMs

Laboratory & ore analysis

Tarkwa's success story

Quality samples equal quality results

Minerals Processing

Events

The customised screens quandary

ON THE COVER p4

Breaking new ground

Engineering & project management

2016

Quashing perceptions

AFR IC AN UPDATES ON THE

GROUND AND UNDERGROUND

DRDGOLD

The era of aggressive returns

TARKWA GOLD MINE

BANIO PROJECT

CUSTOM SCREENS

Excellence breeds success

Licence to mine

The African quandary

ISSN 1999-8872 • R50.00 (incl. VAT) • Vol. 09 • No. 04 • April 2016

Despite having access to a finite resource, DRDGOLD has managed to produce significant investor returns.

@mining_news www.facebook.com/pages/ Mining-News

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editor's comment

Publisher Elizabeth Shorten Editor Mientjie Kleinhans Assistant editor Mpinane Senkhane Head of design Beren Bauermeister Designer Ramon Chinian Chief sub-editor Tristan Snijders Sub-editor Morgan Carter Contributors Ryan Blumenow Client services & production manager

An evolving science

Antois-Leigh Botma Production coordinator Jacqueline Modise Marketing & digital manager Philip Rosenberg Financial manager Andrew Lobban Administration Tonya Hebenton Distribution manager Nomsa Masina Distribution coordinator Asha Pursotham Printers United Litho Johannesburg Tel: +27 (0)11 402 0571 ___________________________________ Advertising Sales

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The millennia-old practice of minerals processing has ever been a vital component of crafting and mining. The process has, of course, become exponentially more complicated in recent years.

Ryan Blumenow compares South Africa to the rest of the world in his article in the economics, finance & risk feature. He writes that an understanding of the ways in which the commodities market has shifted yields insights into how commodities producers may insulate themselves from declining market conditions. This interesting article is on page 8.

rom a time when man had

We also take a look at the Tarkwa

to physically break rock with

gold mine in Ghana. This mine won

implements, to an era of so-

the country’s Mine of the Year award

phisticated science, minerals

and we ask the general manager how

Annual subscription:

processing has evolved over many

it managed this and what the award

South Africa: R550.00

centuries. Today, minerals processing

means for the mine. It turns out that

(incl vat & postage)

still involves the crushing of ore but,

hard work and business improvement

now, with machinery, hydrometallurgy

have much to do with the mine’s se-

and pyrometallurgy, before the final

cret to success.

African countries: US$80 Foreign: US$100 Email: subs@3smedia.co.za ISSN 1999-8872 Inside Mining

product is delivered.

Then, still with gold mining, we speak

In this issue, we look at the various

to the CEO of DRDGOLD to find out

factors of minerals processing, labo-

how this company has managed to

ratory and ore analysis, engineering,

yield great results in difficult financial

protected and may not be reproduced either

project management and consulting.

times. Read more on page 4.

in whole or in part without the prior written

In the latter feature, we talk to spe-

In our underground development,

permission of the publisher. The views of

cialists in the field of consulting to hear

shaft decline and tunnel develop-

contributors do not necessarily reflect those

why relationships between consultants

ment section, we take a sneak peek

and mining companies are important.

at a new drilling technique launched

One of the biggest factors that came

at Africa Mining Indaba. Although still

from this article is trust. Where there is

in the production phase, the com-

a good client relationship, the mining

pany has revealed some interesting

companies trust consultants to solve a

information about this technolo-

problem for them.

gy. Interested? Turn to page 20 for

of the publishers.

To our avid readers, be sure to sign up and get the latest updates and inside scoops from the mining industry. Check out what we are talking about on our website and Facebook page, or follow us on Twitter and have your say.

To read how expertise assists con-

more information.

sultants to solve problems for mining

For all the above news and more,

companies, turn to page 24. Another

sit back and enjoy our latest edition.

interesting discussion in this issue is

And don’t forget to go online for daily

whether customised vibrating screens

news of the mining industry by

are the answer to mining companies’

visiting miningne.ws.

minerals processing. Read what the @mining_news www.facebook.com/pages/ Mining-News

experts have to say about customised vibrating screens, and the applications thereof, on page 14.

Mientjie Kleinhans In sid e M in in g 0 4 | 2016

cover story

The era of aggressive returns With a business model like no other, debt-free DRDGOLD has positioned itself as an aggressive dividend payer despite limited resource optionality and a defined life of mine. CEO Niël Pretorius discusses the company’s enviable success and what the future holds amid a booming gold price.

ullion producer DRDGOLD has

the amount of electricity that DRDGOLD

it’s important that these workers are fully

seen some incredible returns over

uses is much lower per tonne in comparison

integrated with society, living within the

the past year due to a combi-

to other mining operations in the region.

surrounding communities, rather than in a

nation of factors, an increase in

“As a percentage of total cost at your typ-

separate mining community.

production following a boom in the gold

ical underground mine, 75% of total cost

“That is a much bigger distinction than

price and the weak rand. Subsequently,

is made up of labour and electricity; with

most appreciate. It becomes difficult for

DRDGOLD shareholders have seen some

DRDGOLD, the figure is less than 50% for

labour unions to act in bad faith, rounding

impressive returns on investment, with the

both, which makes for a slightly healthier

up and possibly intimidating employees

self-proclaimed high-dividend payer living

model,” Pretorius describes, adding that

living in a single area,” Pretorius explains.

up to its promise. Niël Pretorius has been

the company is, however, more exposed

CEO of the company since 2009, and is

than others at the cost of chemicals

savings, which Pretorius attributes to the

optimistic that the “small” gold producer

per unit.

company’s operations, “Moving items

can look forward to some big returns. Describing the somewhat unconventional

Labour woes?

DRDGOLD also boasts significant power

horizontally consumes far less power than moving them vertically; hoisting uses far

business model, “It is different in some very

Pretorius indicates that, because the op-

more electricity per unit.” He adds that a

important aspects. We do not do any un-

eration is essentially the movement of a

vast amount of electricity normally goes

derground mining; we process and do the

stockpile, the company has managed to

into underground ventilation, which

cleaning up of tailings in and around the

mechanise the process significantly, with a

DRDGOLD doesn’t need.

Johannesburg area,” Pretorius explains.

much lower number of labourers than that

Some major components of DRDGOLD’s

DRDGOLD moves two million tonnes a

of a conventional mine. This differentiates

strategy relate to optimising extraction

month, more than any other mine in South

DRDGOLD from other gold producers, miti-

efficiency, narrowing in on research and

Africa. This is because the miner deals solely

gating labour unrest, a big risk factor in the

development, keeping an eye on technol-

with tailings, which has a very low gold con-

South African mining industry. “The labour

ogy improvements and upskilling its labour

tent. Another distinction is that of power;

we do have is mostly at operator level, and

force. “We have a knowledge-based

Ins i de Mi ni ng 0 4 | 2 0 1 6

”

labour force, with a more intellectual

DRDGOLD’s share price went from R1.80

contribution than a physical one. This is a

last year August to R6 in mid-March 2016 –

very important aspect of our strategy,”

a narrative many gold producers in South

he emphasises.

Africa share due to the weak rand and the high gold price. “I think most local

DRDGOLD’s operations are

gold producers are enjoying a

specifically in and around

significant improvement in mar-

Johannesburg, placing the

gin at the moment. And we

in largely urban areas.

will enjoy it while it lasts; it is

Pretorius states, “It is very

making us all look very clev-

relook at what we can introduce into the

important that our envi-

er,” Pretorius chirps.

plant in order to cover costs and yield a return. A very large percentage of tailings

Due to the fact that

Niël Pretorius, CEO, DRDGOLD

sophisticated, and that we

that we left flattens out at about 0.26 g

DRDGOLD has a “limited re-

maintain appropriate dust

source,” the company has limited

levels and the like. “We have

growth opportunity. Pretorius explains

yet; but the improved recoveries we are

mental containment than we have on div-

as growth companies or resource investors.

getting in the plant provide various options to access some of our lower-grade dumps.

“We are on a defined resource and a

environmental spend in the last seven years

defined area – we know where the deposits

We have four to five hundred million tonnes

at between R850 million and R950 million.

are. It is a finite life with a finite expectation.

of these left over, which we can use to

The results have been worth the spend and

The only way we can differentiate ourselves

extend our life of mine,” Pretorius explains.

we have set out to literally halve dust emis-

against the excitement of new discoveries is

Through upping the volume profile mar-

sions each year,” Pretorius continues.

by clearly indicating that if you invest R100

ginally and further improving extraction

in our stock, we will aim to give you a cash

efficiencies, DRDGOLD can significantly

reward of at least R5 for holding the stock,”

extend its life of mine.

At a results presentation earlier this year, Pre- he details. DRDGOLD investors also see eqtorius indicated that DRDGOLD had official-

uity growth in proportion to movements in

ly entered an “era of aggressive returns”.

the gold price, the best investing opportuni-

tive as it is at the moment. “In November,

“This means we are intent on increasing

ty for the conservative investment maverick.

on average we got R483 000/kg; now it’s trending around R600 000/kg. For a com-

model is different from your typical mine.

Life of mine extension

Once our capital is spent, sustaining capex

During the Investing in African Mining Inda-

gold per quarter, the quarterly swing in rev-

per unit ounce is much lower than that of a

ba in Cape Town, Pretorius indicated that

enue is therefore almost R130 million. For a

conventional mine.

the company was looking at extending the

small company like ours, this has a massive

life of mine, from 8 to 20 years. Expanding

impact,” Pretorius says.

A conventional mine spends at least $150

pany that produces just over a tonne of

per ounce, while our sustaining capex is

on this, he detailed the plan to attempt to

closer to $15 per ounce. So, with most of

increase output from the tailings on hand.

DRDGOLD is in an incredible positon. Preto-

our big infrastructure capex behind us for

Having recently paid off all of its debt,

“Essentially what has happened is the

rius is cautiously optimistic about the future

the foreseeable future, the recent increase

flotation and fine grind is giving us a very

but is all too aware that the current state of

in gold price has really opened up margins

good sense of what the extraction capacity

affairs may change.

quite significantly and we want to pass that

is of our circuit. We don’t leave more than

on to the shareholder,” he says.

0.13 g/tonne behind, which means we can

This is a very cyclical business and a vul-

RESOURCE OPTIONALITY RESOURCE OPTIONALITY 800000 1 1800

DRDGOLD made the strategic shift from high-risk, deep-level Total tonnes vs in situ grade Total tonnes vs in situ grade mining to mine dump retreatment

1 1600 600000

Brakpan 622 Mt @ 0.20 Brakpan 622 Mt @ 0.20 200 Mt @ 0.20 1 1600 600000 Daggafontein 200 MtDaggafontein @ 0.20

1 1400 400000

200000 1 1200

600 600000

400000 400

200000 200

well, you can become complacent and start thinking that this is normal. It’s not and very focused on costs, risk exposure, labour and electricity. We plan to keep our foot on the accelerator production-wise, manage the grid and stay proactive on water. That’s

1 1000 000000

600 600000

“At the moment things are looking good for the industry. But when things are going

therefore one’s outlook needs to remain

Current off at 1.8 Mtpm @ R453 276/kg Current cut off at 1.8 Mtpmcut @ R453 276/kg

800000 800

nerable one at that, with so many things beyond one’s control that can go wrong.

Table 1 Resource optionality

Tonnes (million)

The overall outlook for 2016 is positive for DRDGOLD, with the gold price as attrac-

our dividend yield. The reason being: our

how simple it is,” Pretorius concludes.

272 Mt @ 0.23 Crown Complex 272Crown Mt @ Complex 0.23 Rooikraal 60 Mt @ 0.23 Rooikraal 60 Mt @ 0.23 off at 2.7 Mtpm @ R450 000kg Projected cut off atProjected 2.7 Mtpm cut @ R450 000kg

(6/L/16) 37 Mt @ 0.25 Grootvlei (6/L/16) 37Grootvlei Mt @ 0.25 (6/L/17 ) 49 Mt @ 0.27 Grootvlei (6/L/17 ) 49Grootvlei Mt @ 0.27 2/L/24 88 Mt @ 0.302/L/24 88 Mt @ 0.30 Marievale 33 Mt @ 0.31 Marievale 33 Mt @ 0.31

Withok

Delmore 2 Mt @ 0.35Delmore 2 Mt @ 0.35

Grade

1.40

1.20

1.00

0.90

www.drdgold.com

Grade Ergo site2016 visit | 1919February 2016 Ergo site visit | 19 February

0.80 1.40

0.70 1.20

0.60 1.00

0.50 0.90

0.48 0.80

0.45 0.70

0.21

0.20

0.22 0.19 0.23 0.20 0.24 0.21 0.25 0.22 0.26 0.23 0.27 0.24 0.28 0.25 0.29 0.26 0.30 0.27 0.31 0.28 0.32 0.29 0.35 0.30 0.36 0.31 0.38 0.32 0.40 0.35 0.41 0.36 0.45 0.38 0.48 0.40 0.50

0.41 0.60

800000 800

“However, we are not mining that just

that other mining companies sell themselves

A new era

1 1000 000000

per tonne.

spent quite a bit more money on environidends, for example. I would estimate total

800000 1 1800

We plan to keep our foot on the accelerator, manage the grid and stay proactive on water. That’s how simple it is.”

company’s operations

ronmental practices are

0.19

Tonnes (million)

cover story

In sid e M in in g 0 4 1 | 2016

Mining news

from around the continent

DEMOCRATIC REPUBLIC OF THE CONGO

DRC mining code revision suspended until metal prices recover The government has suspended consideration of a new mining code until met-

prolonging the bleeding of revenues

many other economic, financial and

in the sector, hindering the support our

mining variables in the process,” Lun-

young democracy needs,” they said

sche adds, referring to the agreement

in a statement that urged the govern-

with the government. The agreement

ment to clarify its position.

is effective from 17 March and will run

The DRC held its first free election

for nine years for Damang, and for

al prices recover, the country’s mines

in decades in 2006. It is set to hold

11 years for Gold Fields’ other mine,

minister said in March. The government

another election in November, when

Tarkwa. Each is to be renewable for an

of Africa’s leading copper producer

President Joseph Kabila is due to step

additional five years.

started a review of the 2002 Mining

down. The country has never had a

Code in 2012, aiming to increase state

peaceful transition of power.

MALI

encountered fierce resistance from in-

in minerals prices “a temporary and

Estimated gold reserves climb to 800 tonnes

dustry, which said new taxes and royal-

random event” and noted the existing

Mali has upgraded its estimated be-

ties would drive away investment.

code was passed when the average

low-ground gold reserves by a third, to

price of copper was about $1 500 per

800 tonnes, enough to maintain current

ed and we are going to continue when

tonne in 2002. Congo produced 995

levels of output for the next 15 years,

the context allows,” Mines Minister Mar-

805 tonnes of copper in 2015, down

Minister of Mines and Energy Cheickna

tin Kabwelulu told reporters in Kinshasa.

slightly from 2014. It also mines signifi-

Seydi Diawara said. The West African

Benchmark copper prices fell 25% in

cant quantities of gold, tin and cobalt.

nation, Africa’s third biggest gold

revenues and tighten regulations, but

“We have said that reform is suspend-

2015 and several mines in the DRC’s copper-producing south-east have cut

The NGOs called the recent decline

producer behind behind South Africa

GHANA

and Ghana, achieved gold output of

However, activist groups urged the

Gold Fields deal may safeguard 2 000 mining jobs

government to revive plans for a new

Gold Fields has finalised a tax and

code, saying the higher revenues it

royalties agreement with the govern-

Revenue from the precious metal

would generate were vital to support-

ment of Ghana that could safeguard

accounts for about a quarter of the

ing a young democracy. A group of

its Damang mine, where around 2 000

national budget. “Mali has established

jobs would be at risk if it is placed un-

a mining sector that, since 2002, pro-

der care and maintenance. The bullion

duces 50 tonnes of gold per year. With

producer said the agreement included

resources of 800 tonnes and produc-

a cut in corporate tax to 32.5%, from

tion at that rate, we have enough for

35%, and a change in the royalty rate

another 15 years,” he said on state

to one based on the gold price, rather

television. Mali estimated its gold re-

than a flat 5% of revenue, effective

serves at 600 tonnes last year. A minis-

from January 2017.

try official said that exploration linked

their workforces.

42 Congolese non-governmental organisations that have been in talks with the government and mining sector said difficult market conditions did not justify delays. “Not doing it now is

However, the company said it had

50 tonnes last year. The government is seeking to increase production to 60 tonnes in 2017.

to Canadian miner B2Gold Corp’s

not yet decided whether to inject

future Fekola mine and London-listed

more cash into Damang, one of two

Hummingbird Resources’ Yanfolila

mines it operates, or suspend opera-

project, among others, was behind the

tions there, company spokesman Sven

increase in reserves.

Lunsche says. “This is obviously a positive input into our decision-making process, though we are considering

ZAMBIA

Glencore to invest $1.1 billion in three new shafts Glencore plans to invest over $1.1 bil-

Illegal mining in the DRC

lion in Zambia to sink three shafts with new technology that will extend the life of mine by over 25 years, its local unit said in March. “We firmly believe that we shall overcome the challenges we face today as a company and become profitable and operationally efficient,” Mopani Copper Mines said in a statement. The investments would be made between

Ins i de Mi ni ng 0 4 | 2 0 1 6

Ivan Glasenberg, CEO, Glencore

ZIMBABWE

The genesis of diamond smuggling in Marange

Diamond smuggling and illegal mining are worsening across Africa

now and 2018,

Government triggered the diamond

and it was

rush in Marange in 2006 in a bid to

expected that

attain political mileage, a report

diamond rush began, with thousands

Mopani would

by Human Rights Watch (HRW) re-

of people from other parts of Ma-

vealed at the time. In a 2009 report,

range district, other parts of Zimba-

titled ‘Diamonds in the Rough: Hu-

bwe, and other countries scrambling

man Rights Abuses in the Marange

for the precious stones.”

be turned into a world-class mining operation by 2023, it said. Glencore was

Diamond Fields of Zimbabwe’, HRW

It said the Minerals Marketing Cor-

fully committed to Mopani and had

accused government of abetting

poration of Zimbabwe (MMCZ) – the

invested over $3 billion in upgrading

illegal mining at the diamond fields.

sole licensed buyer of diamonds until

infrastructure and in major capital ex-

“The government effectively fos-

January 2009, when it was replaced

pansion programmes since 2000,

tered the diamond rush at Marange.

by the Reserve Bank of Zimbabwe

Mopani stated.

In an apparent attempt to get po-

– appeared to have encouraged

An electricity shortage in Africa’s

litical mileage from the discovery,

the view that the government tol-

second biggest copper producer and

Zanu PF authorities, in June 2006, de-

erated illegal mining by purchasing

weaker prices have put pressure on

clared the diamond fields free and

diamonds from unlicensed local

Zambia’s mining industry, threatening

open to anyone wishing to look for

miners, in violation of the Precious

output, jobs and economic growth.

diamonds,” it said. From July 2006, a

Stones Trade Act.

In sid e M in in g 0 4 | 2016

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Economics, finance & risk

SA vs the world Understanding how the commodities market has shifted, post financial crunch, reveals important insights into how commodities producers may insulate themselves from declining market conditions. This also allows us to discern how producers, assisted by a complex set of environmental drivers, may exacerbate the downcycle. By Ryan Blumenow

BELOW Ryan Blumenow, economist, Eunomix

greater internal efficiencies. This can be seen by the fact that companies in the

have changed, and become more

same market/commodity segment have

complicated, with certain factors such

vastly different fortunes. There are, how-

as long-term contracts shifting from co-

ever, important regional and compa-

incident indicators of performance to

ny-specific effects at play. Therefore, the

lagged indicators. This forces optimisation

choice of performance metric around

to rely on longer-term market projections

which a producer optimises by setting

and strategic decision-making

internal strategy, structure, and opera-

to be underpinned by ro-

tions matters even when market com-

bust empirical research.

modity prices are a dominant predictor of performance. Generally, our analysis shows that inter-

Additionally, the market has become more

national firms behave differently to South

risk-averse, and

African producers – although there are still

investors are

some external forces at play, their sources

increasingly con-

are different. In South Africa, exposure to

cerned with the

movements in the rand is an important

cost base of the

determinant of performance, and can

PGM producers. Inter-

actually be used as a partial hedge to

nationally, strategy can

commodity price movements. Interna-

no longer be ad hoc and determined

tionally, there is also a different production

purely by market factors, such as con-

and revenue profile that changes the

sistent increases in production, but must

o this end, it is important to under-

product-market diversification internally

be guided by an empirical framework

stand how internal dynamics can

and, thus, the sensitivity to the vagaries of

that takes into account internal factors,

be optimised to improve resilience.

the market. This results in different pre- and

external forces, market sentiment, market

To do this, a research study into

post financial crisis behaviour.

position, and other factors. Long-term

the internal and external drivers of per-

In particular, large international pro-

contracts become strategic tools, even

formance of PGM producers was com-

ducers are more resistant to the business

though investor sentiment in the post

missioned. The objective of the research

cycle and somewhat less volatile in the

financial crisis world causes complicated

is to determine how closely performance

face of unplanned shocks in the external

strategic challenges.

is tied to vagaries of commodity cycles,

market. This means that both regional

and to understand the extent to which

and company-specific factors play a role

long-term contracting is a way for senior

strategy matters.

in determining performance.

management to wrest some control

It also seeks to understand whether

access to technology and enabling

Managing this effect by engaging in

back from the market and allow internal

South African producers face unique

Long-term contracts

choices relative to the rest of the world.

Based on our analysis of the impact of

termining company performance and

As expected, commodity prices are

the financial crunch, we can see that the

value, instead of leaving the fate of the

found to explain much movement in the

market for PGM products has changed.

company to the vagaries of the market.

performance of PGM producers. But sav-

The relationships between explanatory

These contracts would also convey a

vy strategy may act beyond this, allowing

variables and PGM firm performance

more global flavour to operations, with

Ins i de Mi n i n g 0 4 | 2 0 1 6

company dynamics to play a role in de-

Economics, finance & risk our analysis showing that greater levels of diversification and more judicious use of internal dynamics smooth the effects of the business cycle and secure more sustainable market positions, especially as commodity prices fall. Overall, companies enacting strategy on the basis of robust empirical foundations are

Realising possibilities...

more aligned to longer-term market forces, working to maximise gains in a boom market but pre-emptively minimise losses in bust markets. This would also provide a platform for these companies to engage with the broader market, including analysts, further smoothing volatility. These contracting procedures can do more than just smooth volatility in

Interesting observations • International firms behave differently to South African producers • In South Africa, exposure to movements in the rand is an important determinant of performance • Large international producers are more robust to the business cycle and somewhat less volatile in the face of unplanned shocks in the external market

the market. One of the decisions faced by PGM producers is the choice of whether or not to continue on a medium- to long-term path of production reductions that subject them to the vagaries of the market and alternate sources of supply (such as recycling). The alternative is a shortterm production hit with a view to reverting production slowly to the mean, over time, through a more sustainable subsequent run-up in output. This rests on the assumption

that PGM producers have relatively more market power than expected, and that production decisions do, in fact, alter the market price. Although sustained increases in production, even when prices are low, are a management decision to attempt to reduce fixed cost per unit output, this short-term strategy effectively keeps prices on a downward spiral. Shocking the market by reducing production dramatically in the short term may induce higher commodity prices, making an easier business case for expansion thereafter.

...from mine to market.

Power of currency The aforementioned swing factor in the rand makes this even more important. The rand has been demonstrated to fundamentally alter the relationships between market forces and performance. South African PGM producers should consider using longer-term contracting not only to smooth volatility in the face of currency swings (almost akin to a natural hedge), but also to pre-emptively optimise (as the effects of these locked-in prices

Resource Evaluation

Mine Planning

Mining & Mine Development

Materials Handling

Environment & Approvals

Transport to Market

Non-Process Infrastructure

will only be felt in subsequent periods). The longer-term trajectory of prices should be considered, and cognisance be paid to the fact that optimisation should take place for subsequent periods and not just the current period. South African producers should consider how they differ to international producers and how they can simultaneously protect from international market forces as well as exploit idiosyncratic domestic features of PGM operation to compete more effectively internationally. Generally, PGM producers have an opportunity to be market-movers instead, through savvy use of production strategies based around robust empirical analytics. Greater engagement

Mineral Processing

Tailings & Waste Management

WorleyParsons adds value through our full scope of services from pit to port including studies, mine planning, impact assessments, permitting and approvals, project management, construction management and global procurement.

countries

148

must be the norm, in order to bring the worlds of production, analysis and evaluation, and market valuation together. This will rely on deeper engagement between producers, analysts, financiers, government and other stakeholders.

Inside Mining 04 | 2016

Smelting & Refining

www.worleyparsons.com

offices

31,400

people

Commodity: Gold & PGMs

Licence to mine Plymouth Minerals recently received approval to mine the Banio Project in Gabon. The project is located only one kilometre from the coast, with a lagoon within the tenement. This offers an ideal shipping transfer point for export purposes. By Mientjie Kleinhans

ithin a market that has

Potash to obtain granted tenure and

was focused on oil exploration. High

remained strong and

complete this transaction. “The Banio

grades of potash at shallow depths

stable over the past two

Project is something rare – it has the

and over large widths were recorded.

years, with an estimated

right geology, with proven potash

The exact chemical composition is

3% increase year-on-year to 2018, pot-

mineralisation inside the tenement,

known through X-ray diffraction (XRD)

ash is a valuable mineral. The principal

is located within a well-endowed,

analysis, but the cumulative potash

potash ore minerals at Banio are sylvite

past-producing basin and has infra-

grade of the broad zones described

(KCI) and carnallite (KMgCl3.6H2O). The

structure solutions. The location on the

project covers an area of 1 244 km2 of

coast and short shipping distance to

prospective potash-bearing sediments

one of the largest markets (Brazil) can-

and is situated within the Congo Basin,

not be overstated.

which spans southern Gabon, the Congo and part of Angola. Adrian Byass,

comes a roadblock (lack of infrastruc-

managing director, Plymouth, says the

ture) for so many bulk commodity

company is pleased to be working

projects anywhere in the world,” says

with Gabonese officials and Equatorial

Byass. The original drilling at the project

The Congo Basin spans southern Gabon, Congo and part of Angola

This geographic advantage over-

Ins i de Mi n i n g 0 4 1 | 2016

The Banio Bridge is just a few years old – an example of the Gabonese push for regional development – and presents a potential outlet point for export purposes

Commodity: Gold & PGMs table 1 Banio drill collars Hole

Easting

Northing

Depth

Dip

BO1

732 561

9 572 093

927.3

-90

BO2

733 155

9 575 354

912.5

-90

BATC-1

725 630

9 592 325

955.6

-90

Coordinates are in UTM Zone 32 South in geological logging is not known.

selected zones was conducted by ELF

“We will be compiling available seis-

Petroleum by drilling vertically to indi-

mic data, conducting some of our

cate that the strata range from flat to

own, and then drilling in 2016. We are

moderately dipping.

aiming to not only confirm previous potash mineralisation drilled during

Commercial

1980s oil exploration at the southern

Plymouth Minerals purchased 100% of

end of the project, but to extend it to a

the shares in Equatorial Potash, which

wider region within Banio,” says Byass.

owns Mayumba Potasse SARL (Gabon).

and development opportunity, and will

Both the Banio Project and Mamana

advise the market on the completion

Project fall under Mayumba Potasse.

of its due diligence shortly. The pro-

Seismic data analysis conducted

“We believe that either project – Banio

cessing of the second potash project

across the project has structural uplift

or Mamana – has the potential to be

held by Equatorial Potash (Mamana) is

targets associated with the formation

a highly valuable asset and will likely

proceeding and Plymouth is confident

of high-grade, sylvite-style potash

significantly enhance shareholder val-

in the administrative process and min-

mineralisation. This subvertical fault-

ue,” says Byass. “Plymoth considers the

erals industry’s regulatory framework in

ing has created zones of enriched

Banio Project an exciting exploration

Gabon,” concludes Byass.

Geological

The Banio Project is ideally sited for export

sylvite mineralisation in the otherwise continuous and consistent mixed carnallite and sylvite.

graph 1 Banio Project in relation to Elemental Resources Project

Location Not only is Banio located favourably for export, it is also ideally sited in terms of infrastructure and access to markets. The Gabonese government recently completed major bridge infrastructure to line separated parts of the lagoon. It is also in the process of completing a large programme of sealed roads to access the town of Mayumba.

Drilling techniques As oil was the original focus of exploration, the sampling was not systematically undertaken and the geophysical logging of all oil wells was conducted. The spot sampling of

“We believe that either project – Banio or Mamana – has the potential to be a highly valuable asset and will likely significantly enhance shareholder value.”

Table 2 Banio drill results Hole

From m

Interval m

Comments

BO1

580

595

Potash/mg salts logged in the Loeme formation

BO2

528.45

489

Potash salts logged, selected samples reported up to 48% sylvite and 80% potash salts

BATC-1

200

Seismic interpretation of salt dome

In sid e M in in g 0 4 | 2016

Commodity: Gold & PGMs

Excellence breeds

success W

Gold Fields’ Tarkwa Gold Mine, in Ghana, recently won the country’s Mining Company of the Year award. Mientjie Kleinhans uncovers the company’s secrets to success.

HILE OTHER mines in

proximately 250 tonnes a day, from the

other factor to the company’s success is

Ghana have been clos-

massive opencast operation that runs

the Business Improvement Department

ing down in a period of

non-stop. Of the 100 million tonnes, 13.5

that integrates with mining, engineering,

financial turmoil, Tarkwa

million tonnes are treated. With a recov-

maintenance, plant and geology. Tar-

ery rate of 97% efficiency, the mine yields

gets and incentives for ideas that save

has managed to improve efficiencies, increase production and still exceed the

costs have been put in place to reward

production profile. In short, the mine has

ideas that save the company money.

managed to grow during difficult times. During 2015, the mine improved pro-

The biggest cost factors for the mine are

Tarkwa Gold Mine, Ghana

costs. “Three years ago, the mine oper-

duction by 5% to 586 000 ounces and lowered operating costs by

ated at $1 300 per ounce, and now we

12% leading to a healthy growth

do so at $900, which means a pro-

in profitability. This growth is the

duction cost reduction of about 30%.

result of hard work, the com-

We managed this in a period

pany’s business improvement

where all prices increased, except

initiative, proper mine planning,

diesel and fuel costs,” says Van der Merwe. The mine started off

innovative ideas, new tech-

as a heap leach operation com-

nology introduced to the mine and the attitude of the work-

bined with carbon in leach (CIL), but it stopped the heap leach op-

force. The mindset of its people comprises the entire philosophy of

erations about two years ago. “As we

continual improvement, working more

progressed deeper, the oxidised ore

efficiently, growing the company and a

became less and less. The old heap

positive attitude.

leach recoveries moved from 60%

Michiel van der Merwe, general man-

to 40% recovery and that is why

ager, Tarkwa, says the mine has also put

550 000 ounces per year. The pits are

we stopped the heap leach

in huge efforts to create and establish re-

about 14 km long, and the fleet of mining

operation,” says Van der

lationships with the communities around

machines include:

Merwe. He explains

its site. “By doing this, we improved our

• 65 dump trucks, ranging from 100- to

that Tarkwa used

social licence to operate. The commu-

240-tonners

to produce over

nities are pretty much part of what we

• 12 excavators

700 000 ounces

do,” says Van der Merwe. That is, after

• 20 dozers

between

all, where the majority of the workforce

• 22 drill rigs

is based. And to put it in his words: “Suc-

• 11 graders.

cess breeds success.”

Production

fuel prices, labour, power and reagent

Business improvement “One of our successes is our owner min-

Tarkwa mines a palaeoplacer orebody

ing operation. We also do our own main-

that is relatively easy to mine and pre-

tenance of the machines. This is part

dictable with consistent grades. The

of why we mine at less than $2.50

orebody is low grade, with an average

per tonne. Our unit cost is low

resource rate of 1.03 grams per tonne,

due to economy of scale,

which is low compared to other mines in

and our plant’s operating

the region. “To make money from that

costs are less than $11

low grade, one has to push volumes,

per tonne,” explains

making it a volume-driven operation,”

Van der Merwe.

says Van der Merwe. In 2015, the mine

He believes

mined roughly 100 million tonnes, ap-

that an-

Ins i de Mi n i n g 0 4 | 2 0 1 6

Commodity: Gold & PGMs the two plants, with 12 million tonnes

equipment in the trucks. “We used to

times, we mine low in the pits; during

of ore each. Due to the high expense,

have many fatigue incidents, which

heavy rains, we mine higher up in the

Tarkwa focused the mining on CIL and

caused death, incidents, injuries and

pits,” explains Van der Merwe. Whatev-

increased the volumes, and last year it

machine damage. This equipment

er the weather, the mining operations

managed to up the volume to 13.6 mil-

monitors fatigue levels and warns the

have to continue.The tailings dams had

lion tonnes through CIL, for the first time.

supervisor in the control room. Since

to be designed with a safety factor in

“This meant a 97% recovery from CIL,

the new installation, we haven’t had

mind due to the heavy rainfall figures.

compared to 40% from the heap leach

a single fatigue-related incident, injury

Van der Merwe says that the dam was

operation. And that extended the mine

or property-damage incident,” says

designed to withstand a 100-year rain-

life to 2028. This proves that bigger is not

Van der Merwe.

storm. “This means we had to build and

always better. Running more efficiently, using CIL at smaller volumes, makes more

Challenges

money,” explains Van der Merwe.

maintain the tailings dam very well.”

Being located in a country such as

Future plans

The processing plant runs with two, big,

Ghana, with heavy rainfall averaging

The year 2028 doesn’t necessarily mean

gyratory crushers that reduce ore from 1.2

two metres a year, poses some chal-

the end of life for Tarkwa. Van der Mer-

m to 300 mm. The 34 MW crushers con-

lenges. As Van der Merwe explains, ex-

we explains that, although the orebody

sume the most power in the comminution

tra rain brings extra considerations, such

goes deeper and deeper, the decision

plant, which runs off grid from Ghana. To

as the environmental challenges faced.

was made to drill only to a certain level

ensure that the mine saves energy and

The mine has been diverting rainwater

for financial reasons. “Apart from the

carbon, it has been educating the work-

as stormwater, which has meant a lot

possibility of going underground, we

force on ways to save where possible.

of design and development to reduce

are also looking for other palaeoplacer

its environmental footprint by keeping

orebodies in the surrounding areas. We

the water clean. “The high rainfall also

would like to stay within reachable dis-

An example of new technology that

means having dewatering sumps and

tance from the plant, which is roughly 15

has saved the mine lives and costs

dewatering plans in place as part of

km. We have seen some very promising

is the installation of driver monitoring

the long-term mine planning. In drier

targets,” concludes Van der Merwe.

New technology

“Running more efficiently, using carbon in leach, is a sure way to make more money.”

In sid e M in in g 0 4 | 2016

MINERALS PROCESSING

The customised screens quandary Choosing the right vibrating screen can ensure an overall saving of up to 40% on costs, without compromising on productivity or quality. Customised screens have been presented as an option for mining applications, but are they really necessary for the African market? By Mpinane Senkhane

ibrating screens divide

Consequently, frequent component

to the apparent specificity and robust

material into several bulk-

failures are a given and operators simply

design and performance. Be that as it

grain-size ranges or separate

consider this upkeep and maintenance

may, the consensus is that a clear under-

material from impurities and

a cost of doing business in the industry.

standing of the difference in design and

foreign matter. Vibrating screens work

However, screen failures can be signifi-

duty for process plant screens, particular-

with directed vibrations and amplitudes,

cantly catastrophic â&#x20AC;&#x201C; depending on the

ly sizing feed preparation in washing and

which are selected based on the prod-

severity of the fault or damage, this can

dense-media separation (DMS) applica-

uct and depending on the installation

result in damage to shafts and other as-

tions, is a non-negotiable requirement,

conditions. There are various compo-

pects of minerals processing, which will

customisedÂ or not.

nents that affect a decision-makerâ&#x20AC;&#x2122;s

naturally drive repairs, cause downtime

choice on vibrating screens. Among

and often have significant cost implica-

other factors to be considered, the

tions. Where a screen needs to be re-

Is there room for customisation in the African market?

screens can separate different fractions

paired or replaced, the likelihood is that

Generally, customisation of any piece of

simultaneously, so the choice of screen

the problem usually lies in the sizes used

equipment in mining applications can

size and dimension depends on the

in the application, keeping in mind that

be seen as the ideal; however, this is not

application. Vibrating screens in mining

these differ for certain applications. To

always possible, given the magnitude

applications are constantly exposed

curb this, some experts have argued that

of mining operations and their applica-

to the harsh elements and abrasive

the use of customised screens should,

tions. Currently, in the African market,

dust, high vibration and heavy loads.

perhaps, be the preferred choice, owing

the most commonly used screen size is

Joest Kwatani vibrating screen for iron ore applications

Ins i de Mi n i n g 0 4 | 2 0 1 6

MINERALS PROCESSING and other applications,”

MBE Minerals complete resonance screen

says Standers.

2.4 m wide. However, for the

The options

coal market in South Africa, it has been established that

Vibrating screen customisation

screens between 1.2 m

varies, and one of the variations

and 2.4 m may potentially

available is the replacement of

be slightly over-designed in

exciter drives with outer balance

terms of their heavy-duty ca-

electric motors. An exciter drive involves

pabilities. Foreign markets, like

a single motor driving through a cardan

China, tend to use screen sizes

shaft – essentially, a gearbox that has

averaging 3.6 m and wider.

counter weights that spin to create thrust

Inside Mining speaks to Mark Houchin,

on the screen. In contrast, an outer bal-

managing director, Aury Africa; Dave

motion, and the nature of the screen

ance motor is typically based directly on

Maver, sales manager, Vibramech; Gra-

surface as well as the screen support.

the screen drive beam. In cases where

ham Standers, product manager: screen-

“Close attention is also paid to factors

customisation is demanded, Aury adopts this method of customisa-

ing, MBE Minerals; Kim Schoepflin, manag-

such as energy consumption, mainte-

ing director, Joest Kwatani; and Etienne

nance requirements, throughput and

tion and Houchin notes that the out-of-

Swanepoel, product specialist, Osborn, for

service life,” says Standers. The compa-

balance electric motors are situated on

some insight on vibrating screen customi-

ny is able to leverage an extensive foot-

the drive beam and vibrate directly on

sation in an African context.

print of screen installations both inside

the screen. “These motors are consider-

and beyond South Africa.

ably cheaper to purchase and reduce

Is customisation the better option?

“All our screens are tailor-made to

“I suppose it all depends on what you are

meet the exact requirements of each

customising and why you are customis-

application and include dynamic

the overall cost of the screen by another 10% to 15%,” says Houchin. Joest Kwatani’s Schoepflin says, “It

ing it. If you are building a custom-built

and static screens for scalping, sizing,

must stand to reason that no standard

screen to suit a client’s particular needs,

dewatering, desliming, trash removal

‘float and sink screen’ can fit all mineral

with regard to the size of the screen, then custom-building it might be a better option as the customer will then have

Kim Schoepflin, managing director, MBE Minerals

ore body characteristics. Yet, standard equipment is often the preferred option in order to reduce design cost, as the

a screen fit for purpose as opposed to

EPCM contractors have already drawn

maybe having too small or too large a

such standard equipment into their DMS

screen,” Houchin explains.

plant, for arguments sake.” She adds that it is, therefore, not surpris-

Osborn offers a wide range of standardsized vibrating screens to cater for the

ing to see that ferrosilicon recovery, as

mining and aggregate markets, with

one of many examples, is not meeting

various vibrating options. “We’ve got

the required reclamation rate in new

everything from the heavy-duty steel-

plants. “Our company’s orebody-spe-

shaft-driven, Obex (twin-motor) Superking

cific processing screens are fully cus-

to the Gbex (gearbox-driven) linear-

tomised, as each screen must meet

motion screens, which are widely re-

the critical aspects of the physical ore

garded as high-speed, high-volume

characteristics and flow attributes that

screens, superior in screening efficiency

are unique in each process application,”

and capacity versus the more conven-

says Schoepflin. Houchin stresses that there is no neg-

tional horizontal and declined models,” Swanepoel explains.

ative impact on quality or efficiency

“All our screens have been tried and

where customisation is implemented:

tested in all applications, so we tend not

“There is no compromise on quality; all

to deviate from our standard range of

we have done is shed some weight and

vibrating equipment. We have a highly trained design team and are currently of the opinion that customised vibrating screens have significant risks associated with them.” In designing its screens, Osborn utilises the latest design technology combined with FEA design analysis. At MBE Minerals, the engineers classify the various designs of screen according to factors such as generation and application of motion, the true vibrating

“Our orebodyspecific processing screens are fully customised; each screen must cater for the site’s physical ore characteristics and flow attributes.”

replaced the exciters with out-of-balance motors to make the screens better-suited for local operations.” At Vibramech, Maver ensures that clients keep in mind that adequate wear and corrosion protection should be incorporated into the design to prolong the life of the equipment. The equipment must be designed for ease of maintenance and to minimize spare parts. Houchin adds that the factors to consider include the type of material

In sid e M in in g 0 4 | 2016

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MINERALS PROCESSING being screened, particle size of the feed,

challenges associated with the custo-

design at Joest Kwatani require two to

feed rate to the screen and the desired

misation of screens. “The footprint of a

four weeks, depending on the scope of

particle size of the product.

customised vibrating screen, in most cas-

the project and customer interaction with

es, isn’t standard, making it very difficult

their design engineers. Depending on the

when shopping for a screen replace-

machine size and type, four to six weeks

The consensus in an application is that

ment. In these cases, most of the time,

are required for fabrication and final as-

any piece of custom-made equipment is

the customer has to carry the cost of

sembly. “The time from the initial design

likely to be significantly more expensive

changing the support steel

to delivery can range

than one that comes standard. Howev-

work to accommodate

anywhere from 6 to 12

er, Houchin suggests that this may not be

the new screen. Where-

weeks, depending on

the case. “If you custom-build a screen

as, when sticking to a

the project. Installation

based on size, it might even be cheaper

standard vibrating screen

and on-site commis-

if you are building a smaller screen than

size, the interchangea-

sioning times are large-

one that is contained inside the normal

bility and replacement is

ly dependent on the

product offerings. Swanepoel indicates

more cost-effective and

contractor or end user.

that, in his experience, there are likely

quicker, resulting in less

Joest Kwatani supports

to be more cost implications associated

downtime.” Schoepflin

the commissioning

with customised screens. “Customised

goes on to warn, “If the

process on-site,”

screens do carry a higher price tag

screens are not specifically

considering the design hours associated

designed with the correct

and the risk to the supplier, who has to

screening parameters of

carry the warranty should the unit fail for

stroke, vertical acceler-

any reason.

ation, drive and deck angles, as well as

that the considerable risks associated with

Cost implications

Hence, when our customers buy a

Etienne Swanepoel, product sales specialist, Osborn

explains Schoepflin.

Conclusion Swanepoel suggests

the correct selection of screening panels,

customised vibrating screens include, but

standard, tried and tested vibrating

positioning of weir and water spray bars,

are not limited to, over- and under-de-

screen, the design has already been

and the correct type and number of

sign. “If the customisation is not done by a

completed, and there is considerably

spray nozzles, it would result in the inef-

specialist in this field, it could have a cata-

less risk to us due to previous supply

fective reclamation of ferrosilica, bring-

strophic effect on production, should the

and testing. With customised vibrating

ing about a huge financial loss to the

vibrating screen fail. And, as mentioned

screens, a much longer lead time can

customer. “Similar cost savings cannot

before, the failure of a vibrating screen

be expected due to the abovemen-

be achieved by the use of standardised

can be a very expensive exercise. “Stress

tioned design time, ” Swanepoel details.

screening machines, as they do not take

relieving of the deck frames and side

the total life-cycle cost into account,”

plates to prevent cracks is only one of

says Schoepflin.

the critical manufacturing processes that

The standard screens Aury Africa and Osborn supply to the market are both adequate and versatile enough to cater for a variety of different applications

Lead time

should be followed, and which are sometimes bypassed to keep costs down. This

The average lead time from design to in-

reduces the life of the vibrating screen

stallation of customised vibrating screens

considerably,” Swanepoel continues.

varies according to the size and quantity

Perhaps as much as customised vibrat-

required. Maver says that individual ma-

ing screens are theoretically a convenient

chines can be completed in six weeks

option, the convenience, like any other

and equipment for new plant projects

application, comes with costs and risks

take 14 to 18 weeks. Standers says that it

that can be deemed unnecessary. The

If it is only the duty or size of a screen

takes MBE Minerals between 10 and 12

standard screens Aury Africa and Osborn

that requires customising, there are no

weeks, while Aury Africa typically takes

supply to the market are both adequate

great challenges involved. But, Houchin

eight weeks from design to completion of

and versatile enough to cater for a varie-

explains, “When a customer requests

manufacture in China, and another four

ty of different applications, including the

screens built from stainless steel, for

weeks for shipping to South Africa.

particularly tricky coal and iron ore appli-

example, there are some special pre-

Schoepflin explains that the process

cations. The choice is yours.

cautions to be taken when welding and heat treating. These translate into cost implications. “A while back, Aury was asked to design some lightweight screens, which is very different to what we usually build, and extra care had to be taken when selecting material for side plates and cross members, to ensure that they were light enough but still strong enough for the duty,” Houchin continues. Swanepoel identifies high price tags and long delivery times as some of the

In sid e M in in g 0 4 | 2016

MINERALS PROCESSING

Saving on every level I

n some cases, saving costs in minerals processing means intro-

In current conditions, every aspect of mining is scrutinised for possible cost-saving techniques. This drive brings along new technologies and ways of doing business. Minerals processing divisions are not untouched by this shift.

BELOW Renira Reddy, business development executive, Minopex

covering various aspects of minerals processing, including: • asset management

ducing new technology that use processing objectives are always priori-

and maintenance

es, professional consulting teams take

tised. We also carry legal appointments,

• plant process control

care of cost-saving factors. Although

as required,” says Reddy. Another

it is not a new concept at all, Minopex

benefit of outsourcing is a reduction

fewer chemicals. In other instanc-

operates and maintains process

in business risk – an advantage

plants for plant owners on a

when a mine needs to free up

contractual basis.

resources so it can focus on

This approach leaves the

core competencies.

operation of the plant

Client requirements

to the experts, so that

and optimisation • contract management and administration • purchasing • stores control • training and skills development • subcontractor management • health and safety

mine owners can fo-

At Minopex, projects

• environmental management

cus on core business

are dealt with on a

• waste and tailings

aspects, according

project-to-project

to Renira Reddy,

basis. “Our systems and policies are

business development

standard; however, we

executive, Minopex.

recruit a new team to

What makes its services

operate each project. We

unique is its ISO accreditation

utilise both internal and external

and that all projects are execut-

dump management.

Conclusion Outsourcing to an experienced company like Minopex not only saves time and costs, but also reduces business and safety risks, while

ed to the highest standards. “We are

recruitment to ensure that our culture

ensuring access to the

uniquely positioned to service both

and way of operating are passed on to

necessary manage-

blue-chip companies as well as junior

new projects,” says Reddy.

ment expertise.

miners. Our in-house operational readi-

The company is geared and opera-

ness capability is a major benefit to our

tionally ready to assist a start-up facility

clients – we can get their projects on-

with the implementation of new pro-

line in the fastest time,” says Reddy.

jects. With the specialised and training

Benefits Reddy says that the benefits to contracting such a professional consul-

teams ready to accelerate a project, the operation can see quicker returns on investment.

tancy company are that clients can

Solutions

keep their overheads to a minimum by

Minopex tailors its service

outsourcing. “We are fully accountable

offerings to each cli-

for our performance, so our clients’

ent’s requirements,

“We are uniquely positioned to service both blue-chip companies as well as junior miners.”

In sid e M in in g 0 4 | 2016

underground development

Breaking new ground Committed to innovation, Master Drilling has introduced a boring system that promises to revolutionise the mining sector by sinking shafts up to 2 km deep in a third of the usual time. Mpinane Senkhane speaks to Louis Germishuys, COO: Shaft Development, about the system and what it offers the mining industry.

or years about 30 years now,

traditional tunnel boring techniques em-

proven technologies combined to

Master Drilling has positioned

ployed to ream the final diameter. The

work together in a unique way, ena-

itself as the global raise bore

boring can be done in rock hardness of

bling an advance rate of 7 m per day,

specialist , providing special-

up to 350 mPa.

compared to 3 m per day in the case

ised drilling services to blue-chip and mid-tier companies in the mining, civil

Meeting a need

engineering and energy sectors. Once

Germishuys explains how the company

again, the company has demonstrat-

identified a need in the global market

ed that there is intellectual property

for a mechanical means to create

to be deployed profitably within the

vertical shafts from the surface, without

mining industry, across a number

bottom access.

of commodities. The Blind Shaft Boring System (BSBS) is a mechanised system, developed by

entiates it from traditional raise boring,

the company, for boring a vertical shaft

where it is required,” he explains.

to a depth of 2 000 m, with finished

“The BSBS fulfils this need and the fact that no bottom access is required differ-

Previously, the idea of boring a shaft

diameters ranging from 10 m to 13 m.

as deep as 2 km in without explosives

Shaft boring is a two-stage operation

may have been deemed impossible.

where slurry boring is employed to do

Germishuys indicates that the BSBS

a pilot shaft of 4.8 m in diameter and

concept has “been designed with

Ins i de Mi n i n g 0 4 | 2 0 1 6

of conventional shaft sinking using drill

Blind Shaft Boring System applications • Mining sector: Shaft boring or enlargement is used for the construction of access or ventilation shafts for the mining industry. The BSBS is suitable for any greenfield or brownfield underground mining application at copper, zinc, gold, iron ore and platinum mines, among others. • Civil sector: In the urban infrastructure industry, it is used for access and ventilation shafts to metro tunnels. • Energy sector: In the energy sector, it is used for surge, ventilation, access and pressure shafts.

underground development and blast techniques.”What particularly differentiates the BSBS system from any other boring approach is that it requires no underground infrastructure. In explaining the concept behind such a system, Germishuys details how the BSBS was the result of identifying a need in the market to have vertical shafts that can be done safely and efficiently with no blasting in the shaft barrel and no blasting fumes exhausted into the atmosphere. This, of course, also has desirable en-

For South Africa, Master Drilling’s innovation offers an encouraging narrative of research and development in the turbulent mining industry and “actually becoming producing

vironmental implications, and allows for

mines”, particularly under different

the system to be deployed in the vicini-

circumstances where underground

ty existing infrastructure.

access is deemed unsafe or inefficient.

For mining, this innovation has several potential implications. “The BSBS will result in safer, cheaper and earlier access to ore-

Such projects might not normally pass, and have historically not passed, the feasibility stage.

bodies at depth. As such,

Business model

the system will reduce the

As per Master Drilling’s

time it takes for a mining

business model, as a con-

project to achieve its

tractor who designs and

steady state of produc-

manufactures its own drill-

tion, thereby improving

ing equipment in the bid to

the project’s NPV and

provide complete drilling

IRR,” he details.

service solutions to the

The BSBS approach offers

markets it serves, its system

clients the prospect of a

will only be available on

positive, overall contribu-

contractual execution

tion to mine production

terms and not for sale or

and logistics and has

lease. The IP has been

the added benefit of

registered and filed, and

facilitating mining-level

currently sits with Master

breakaway operations

Drilling. Germishuys says the

and simultaneously lining

manufacturing of the sys-

the shaft with pre-cast

tem will be completed by

concrete segments, as

Q1 of 2018.

well as enabling diameter/ depth changes without major modification. “That means that access can be

“Master Drilling will be manufacturing the system at risk, meaning that any potential client would not have

provided to mining machinery to ex-

to place an order for the system to be

cavate the mining level with mech-

manufactured. We believe it is essential

anised equipment after the shaft

to have some ‘skin in the game’ and

has been bored. This ability is unique

have the system available when the

to Master Drilling’s BSBS design,”

client wants it,” he adds.

Germishuys continues. He emphasises that, with the BSBS,

With the procurement process currently under way, Master Drilling says it has

projects have the increased poten-

identified various possible suppliers and

tial of meeting the required hurdle

expects an award to be made by the

rates imposed by mining companies

middle of 2016.

OPPOSITE (left to right) Danie Pretorius, CEO and founder, Master Drilling; Louis Germishuys COO: Shaft Development, Master Drilling; Murray McNab, global director: Mining and Mine Development, WorleyParsons; Steve Gouws, head: Mining Engineering, WorleyParsons; Koos Jordaan, technical director, Master Drilling

such an innovation is an encouraging

For South Africa, the development of narrative of research and development in the turbulent mining industry – one we can safely call groundbreaking. “It can be described as such, with the added distinction that it is truly South African.”Germishuys concludes.

I n s i d e M i n in g 0 4 1 | 2016

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engineering & project management

Turnkey solutions Mining will be a business of the best, not the biggest. And the best will need to resolve certain factors.

hese factors include more efficient and sustainable operations,

for Africa

Wilhelm Swart, vice-president: Mining Minerals and Metals

a higher investment in R&D and the use of technology, a more

delivery of Schneider Electric’s MMM turnkey solution to customers throughout Africa,

monitoring,” explains

we have set up offices in

disciplined capital allocation, and in-

Swart. He says that the

23 locations covering all

creased focus in cost management,

company’s electrical

54 countries and terri-

operational excellence and value

distribution safety and

tories, with six execution

creation. Currently, Africa’s mining,

arc flash mitigation

centres delivering our

minerals and metals (MMM) industry is

solution encapsulates

experiencing various challenges that

arc-resistant equipment

need to be addressed in order to en-

and electrical safety services,

sure operational sustainability.

electrical safety compliance servic-

and service centres in Africa, and more

es, and power system assessments.

than 120 field services employees and

“Schneider Electric offers turnkey solutions that not only help solve these

The solution also addresses reliability

solutions across the continent. We have 300 engineers dedicated to project centres

a total of 3 000 employees. To date, we

challenges, but also enable operations

issues, process disruptions, code vio-

have the largest and most sustainable

to grow in a sustainable way, obtain

lations and outdated workplace safe-

partner network in Africa, including

the most of production resources and,

ty requirements. “Further, an important

2 800 points of sale, more than 500 inte-

above all, increase overall efficiency

aspect of our lightning detection solu-

grators and 8 000 electricians. We can

to drive new revenue streams so that

tion is that it provides real-time lightning

transform your operation to be the best

our customers gain the competitive

data, not predictions – a valuable tool

in Africa,” concludes Swart.

advantage over business rivals operat-

for organisations operating in Africa,

ing in the region,” says Wilhelm Swart,

where lightning storms are common

vice-president: Mining Minerals and

and can have devastating effects,”

Metals. Schneider Electric has encapsu-

continues Swart.

lated its MMM solutions into four pillars:

Supplementary tools to address safety

1. Safety and security – to improve

and security in MMM operations are

sustainability by enabling zero

Schneider Electric’s video analytics,

incident operations

which, through constant, automated

2. Social licence to operate – to

digital screening and filtering, can

obtain and maintain the li-

identify specific conditions and notify

cence to operate by creating

operators of potential situations.

shared value while taking care of the environment 3. Operational efficiency – to strength-

Maximising value creation Unifying the value chain, Schneider

en people effectiveness, optimise

Electric offers customers an integrated

use of assets and increase produc-

planning, scheduling and optimisation

tion performance

solution that, among others, enables

4. Maximise value creation – to unify

an operation to deliver to the market

the value chain and so achieve

the right quantity at the right time,

business optimisation

grade, quality and cost. Also included

Safety and security

is business process management and workflow software, an application

“Our process safety solution offers cus-

that enables companies to automate

tomers hot standby systems, SIL2/SIL3

processes that include people, oper-

and triple-modular redundant architec-

ational and business systems. The solu-

ture. From a machine safety perspec-

tion further comprises trading and risk

tive, customers are offered safety con-

management, asset management, a

trollers, perimeter guarding, emergency

fuel management system and energy

stop technology, and speed and guard

procurement services. “To guarantee

www.schneider-electric.co.za/en

In sid e M in in g 0 4 | 2016

engineering & project management

Unbreakable bonds Understanding client needs and building trust form the bases of both customer loyalty and quality client service, which are vital in today’s competitive business world. By Mientjie Kleinhans utting costs and increas-

views and thoughts from the tradition-

them to make the best-advised choices

ing production are two buzz

al that could benefit the mine in terms

in today’s rapidly changing market.” He

phrases recently emanating

of cost saving on equipment selection

adds that relationships are critical to the

from company boardrooms.

and ongoing running costs,” adds Mark

success of the mining industry.

Houchin, managing director, Aury Africa.

where they can, while striving to increase

“Mining companies are trying to cut back

work effectively, one needs to be able

production. All the while, consultants assist

on costs. By working closely with them, we

to trust the people with whom one works.

mining companies where they can in an

are able to better understand their needs

“It is central to our vision, which is to be a

effort to stay afloat, which is beneficial to

and offer better advice or alternative sug-

trusted partner to our customers.”

both parties.

gestions to what they might have arrived

The major benefit of working with con-

at on-site,” says Houchin.

Rolf Redelinghuys, national market manager: Mining and Minerals/Roadmarking,

sulting companies is making use of their

He adds that relationships are important,

Plascon, says that although they supply

experience and expertise. George Ben-

especially once the mining company real-

directly to mines, they also fulfil the role

nett, business development director, MDM

ises that the supplier has specialised knowl-

of consultant. “I think the big thing is

Engineering, says that consulting compa-

edge and is willing to help at all times.

that we have the full capability to also

nies are valuable in that they employ a

offer products and technical advice to

wide variety of highly skilled staff, who are

Vital relationships

used for the growth and development of

Bennett explains: “Gone are the days

mines, projects and so on. “The benefit

when service providers were at arm’s

trial Coatings, Plascon, adds that the

to mines is that they no longer need to

length from their customers. The industry

company has people with more than

employ these skills on a permanent basis,

has changed and the pace at which

35 years’ experience. “We have a lot

but can rather utilise the skills of consulting

mining companies need to respond to

of technical expertise in our company,

companies when needed,” says Bennett.

these changes has increased significantly

which we make full use of to asses and

from a few years ago. Our primary goal

solve challenges.”

“We have specialist knowledge and

Business is built on trust and, in order to

Mining companies are cutting costs

should be aware of new developments in

has been to understand our customers’

our chosen fields. We might have different

concerns and how we can better position

Ins i de Mi n i n g 0 4 | 2 0 1 6

mining companies.” Dale Maurer, market manager: Indus-

As a specialist supplier of equipment, consulting companies might be in a

engineering & project management better position to propose better-suited

completed and in a better position to

equipment than the mine, according to

attract investors for execution.” Bennett

Houchin. “We are also likely to be aware

adds that there is no one-fits-all approach

of new technological developments that

and that it should be assessed on a case

could help increase production.” He adds

by case basis to determine what the best

that they prefer it when mines specify a

factors are to reduce costs.

particular challenge, requesting proposed solutions to the problem. “Every orebody, mine and project is

Special offerings Just as mines are unique, different con-

unique. While many have similar charac-

sulting companies have unique offerings

teristics, no two are alike, so why would

that could fit in with mines’ requirements.

one treat them the same? In a time

The trick is to find the right fit. Aury Africa

where the market is particularly focused

has technological backup in both Aus-

to draw upon the skills of 40 000 people

on maximising efficiencies and profits, tai-

tralia and China and, as such, is able to

across 55 counties,” claims Bennett.

loring the solution to their needs may just

offer alternative solutions to problems that

benefit that little extra, which changes the

might not be available in South Africa.

game completely,” explains Bennett.

Saving costs

“Our Chinese support, in particular, is familiar with a wide range of equipment – from a broad spectrum of

BELOW George Bennett, business development director, MDM Engineering

Redelinghuys says that, as South Africa’s biggest coatings manufacturer, “Plascon is particularly attractive to the mining industry as we are a one-stop shop and an exceptionally well-known brand throughout Southern Africa. We

Saving costs is a ubiquitous ambition in

suppliers – and offers us

the industry, at every step. Aury Africa

support on many other

have factories across Southern

assists mines with costs on the equipment

OEMs’ equipment. We

Africa, and have been sup-

brought in from China, due to the low

also pride ourselves

plying to Zambia, the DRC,

manufacturing cost base. “Our company

on our local technical

Botswana and Namibia.”

is the largest manufacturer of vibrating

support and response

screens in the world and we benefit from

time to any problems

the resultant economies of scale. This is

– be it with our or any

being eroded to some degree by the

other OEM’s equipment,”

worsening rand/dollar exchange rate,”

says Houchin.

says Houchin. Bennett says that one of MDM Engineer-

MDM Engineering offers the entire val-

Conclusion Close relationships with consulting companies and supplier consultants assist mines are key to optimising operations and overcoming

ue chain to customers – from ESIA and

challenges. Consultants have the exper-

ing’s strengths is plant and operational

geology to mining, process plant and

tise in a particular field and will go out

optimisation, which results in an overall

more. “This enables a more holistic ‘big

of their way to assist mining companies

cost saving. “Added to this, we also look

picture’ approach and provides greater

where they can. All of this helps to build a

into innovative ways to keep our cus-

opportunity to realise wholesale benefits

strong relationship between customer and

tomers’ costs down using funding from

from all areas. We also have a significant

supplier, which builds a trusting and lasting

third-party sources to get their studies

geographical footprint, with the ability

relationship to solve problems together.

“Our primary goal has been to understand our customers’ concerns and how we can better position them to make the best-advised choices in today’s rapidly changing market.” In sid e M in in g 0 4 | 2016

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Hydrometallurgy

In the paper ‘The behaviour of free gold particles in a simulated flash flotation environment’, the authors report on and discuss their findings after having researched and performed a test on free-milling gold ores and synthetic ores.

Assessing gold particle floatability

n the synopsis of the paper, the au-

residence times. It was shown that the ulti-

was on the comparison of free gold and

thors – TDH McGrath, JJ Eksteen and J

mate recoveries and kinetic trends of gold

pure gold powder recoveries as a function

Heath – state the test was conducted

particles from the gravity concentrate

of collector PAX addition.

by using either a gravity concentrate

could be enhanced with an increased

or gold powder as the gold source to

dosage of a collector, potassium amyl

Flash flotation relationship

assess the floatability of gold particles.

xanthate (PAX),” write the authors.

According to the authors, when both

“Trends in free gold flotation kinetics,

The research aim was to identify param-

gravity concentration and flash flotation

as well as size and milling effects, were

eters that may determine whether free

are employed in a milling circuit, flash

identified for gold recovery based on the

gold particles will be received between

flotation can be used in parallel, series,

different feed types, reagent dosages and

212 µm and 38 µm. The focus of the study

or cleaning arrangement with batch

Ins i de Mi n i n g 0 4 | 2 0 1 6

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Hydrometallurgy centrifugal concentrator (BCC) units. In a cleaning application, the flash flo-

test work. One contained BCC gravity concentrate, created by blending multi-

gravity-recovery gold

tation cell creates a sulfide concentrate

ple concentrates from primarily Australian

that is then secondarily treated by gravity

sources, split into 5 g subsamples yielding

recovery with removal of gravity-recov-

head grades of about 13 g/t to 16Â g/t

erable gold (GRG) from the bulk sulfide

when added to silica. A bulk assay of the

concentrate. In series, the BCC treats a

BCC concentrate established that the

portion of the flash tails, while in parallel,

concentrate had a gold-to-silver ratio of

the flash and gravity units share the same

9:1, although scanning electron micros-

feed, usually the cyclone underflow, and

copy demonstrated that individual gold

to extinction while splits of the tails sam-

the tails streams are returned to the milling

particles vary greatly in their ratio and

ples were subject to both fire assay and

circuit to close the loop. In the parallel

placement pattern in the particle.

intensive cyanide leach by rolling bottle in

GRG refers to free gold reporting to the concentrate stream with a small mass yield if separations are performed using batch centrifugalÂ concentrators. Concentrate samples were fire-assayed

arrangement, the nature of the particles

The second synthetic ore was created

order to better close the mass balances.

recovered to each unit and the factors

using the same silica blend as the first, but

The authors write that because the mass

affecting recovery of the GRG are not

used synthesised, pure gold powder to

of gold in the test was either known, in the

completely understood, due to the inter-

obtain a head grade of 30 g/t to 40 g/t.

case of the powders, or calculated, in the

action of many complex factors.

The tests were repeated on 1 kg charges

case of the concentrate, inconsistencies in

six times for each condition, to produce

the gold and mass balances are attribut-

enough combined concentrate mass to

ed to the nugget effect in the coarse and,

The authors describe, in great detail, how

be screened into the three size fractions

to some extent, intermediate tails samples.

the experiment was conducted, starting

ofÂ interest. The replicate tests ensured that

The full paper can be found at the ad-

with gold from two sources being floated

average masses and concentrations re-

dress on the link below.

according to the free gold flash flotation

ported were statistically representative.

Experimental method

test, with PAX addition and gold type be-

Each set of six conditions produced

ing the only variables. Two synthetic ores

seven concentrates and a tails sample,

were created for the laboratory flotation

all of which yielded 21 samples per test.

FOLLOW THE LINK Unedited technical paper: http://bit.ly/1QUe1cD

In sid e M in in g 0 4 | 2016

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laboratory & ore analysis

Quality samples equal

quality results In mining applications where ore sample sizes wouldn’t fill a teaspoon, the better the sample, the better the results. Mientjie Kleinhans investigates the science behind ore sampling for better analysis.

ifferent analytical appara-

regularly (on a timed or mass basis) by

material stream at right angles and at less

tus require different ore sample

cross-stream methods to achieve accu-

than 0.6 m/s speed with parallel cutter

preparation, leaving it up to

rate final samples,” says Steinhaus. He

blades and associated widths of greater

the manufacturer and supplier

adds that sample integrity, in addition,

than 30 mm for fine solids,” says Steinhaus.

to specify the ideal procedures. Seeing

also hinges heavily around the sampling

“Furthermore, the equipment, once

that there are various systems for different

of one-dimensional streams, such as from

correctly designed, needs to be installed

applications, differing in sample sizes,

conveyor belts and vertical chutes or

and integrated into new (greenfield) or

mining companies need to keep certain

pipe columns, for dry or wet slurry appli-

existing (brownfield) plants. Sample cut-

factors in mind.

cations respectively. Access to all parts

ters must intersect the material streams

of the ore material body needs to be

fully and ensure no blockages,” explains

director, Multotec Process Equipment,

guaranteed and then random samples

Steinhaus. He adds that correctly installed

explains the influence the quality of ore

can be obtained using recommended,

equipment then needs to be maintained

samples has on analysis. “Mineral ores

industry-stipulated guidelines and equip-

properly with regular, planned mainte-

that are being crushed, milled, then ei-

ment designs.

nance interventions to prevent longer-

Rolf Steinhaus, sampling specialist and

ther separated or leached, concentrated

“Each particle passing a specific point

term mechanical breakdowns.

or beneficiated in process plants daily

in the process plant must be given an

are very heterogeneous in nature, in

equal opportunity of reporting to a com-

lines in the equipment operating and

terms of the levels and types of naturally

posite sample collected over a period of

maintenance manuals. We cannot

occurring elements and chemical con-

time. This minimum requirement should

expect good sample collection from

stituents. It is of paramount importance

never be neglected. Some 80% to 90%

neglected or worn sampling equipment,”

that these ores are sampled sufficiently

of sampling errors occur well before

says Steinhaus. He further explains that

analytical processes and need be a

daily operator inspections are also rou-

point of focus for any design or process

tinely recommended to ensure there is

engineer serious about introducing ‘cor-

no build-up of foreign material on sample

rect’ sampling solutions into a plant,”

cutter apertures and to ensure conse-

says Steinhaus.

quent occluded cutter blades do not

A cross-stream, multistage sampling plant

Improving ore sample quality

“This should be done as per the guide-

become a source of bias.

End users of sampling systems need to

Products and technology

ensure that the mechanical samplers

To improve the quality of ore samples,

they purchase are not only cost-effective,

there are cross-stream sampling tech-

but that the inherent designs emphasise

niques and mechanical sampler equip-

the required integrity, according to Stein-

ment to ensure final sample integrity.

haus. “Lowest-cost procurement is not

Steinhaus explains that these systems can

a route to quality! Aspects of the cutter

be either a single-stage, cross-cut sam-

arrangement that traverses the full ma-

pler for smaller plant throughput for fine

terial stream need to define and extract

material ores, or multistage systems for

the full portion of that sample increment

high ore flow rates, which will have addi-

without misplacing particles as it does

tional equipment such as crushers, sam-

so. Belt-end, cross-stream sample cutters,

ple dividers, sample dosing feeders and

for instance, need to traverse the entire

sample collection carousels arranged

In sid e M in in g 0 4 | 2016

laboratory & ore analysis sequentially to provide manageable final

data for optimising process effi-

sample sizes for each consignment or batch.

ciencies, is also often desirable.

“These final samples need be representative

Importantly, these are trend-

of the consigned material, whether it repre-

ing technologies using control

sents a shift period, 24 hours of production,

sampling and not metallurgical

or train/ship loads. When sampling bulk com-

accounting. The latter requires

modities like coal or iron ore, adherence to

more reliable values with lower

long-established ISO sampling standards is

levels of uncertainty (thus high

essential,” asserts Steinhaus. He adds that on-

precision) to ensure monthly

line analysers with continuous offtake devices

mineral balancing of complex

for ore slurries, or mounted, over-belt convey-

metallurgical circuits is properly managed and adheres to the

ors, are still only considered for control (not metallurgical accounting) sampling applications such as at base metal concentrators.

A primary and secondary iron ore sampling plant

central tenets of corporate governance and associated official reporting,” says Steinhaus.

Bad sampling

Lab analysis

Sample delineation, extraction, weighing and preparation errors are

In the laboratory, ore sampling is done on a different

common sources of bias and can be eliminated by correct designs

scale. Yet, the same rule applies where better-quality

and sampling techniques, according to Steinhaus. “Errors emanating

samples result in better results. Dr Ljiljana Marjanovic, an-

from short- and long-term periodic process fluctuations, material seg-

alytical technical specialist, SGS South Africa, believes

regation due to density and grouping effects, and mineral variability

that sampling forms an integral part of the analysis and

due to ore lump sizes are more difficult to control and these sampling

it is often referred to as the most difficult step in

errors can only be minimised,” explains Steinhaus.

analytical processes.

Latest technology

be meaningless if the wrong sampling is performed.”

He explains that over-belt, online analysers are increasingly being

She adds that only a very small portion of the sample

used for monitoring crushed or milled ore materials in the coal, iron

is analysed in the lab and it is, therefore, very impor-

ore and cement industries. This gives continuous, real-time analysis

tant to understand that the sample must resemble the

and immediate results, overcoming the time lag of conventional

“population” it represents as closely as possible. “This is

sample preparation and analysis delays associated with mechanical

applicable to the whole process, starting from the iden-

sampling systems. It can be seen as an attractive option for plant

tification of the population, gross sample collection, the

operators to help maximise their product yields and even out quality

reduction of gross sample size to laboratory sample size,

spikes, and is particularly useful for the trending of values of minerals

as well as particle size reduction and sum sampling in

or the ore grade of interest. “Monitoring qualities of base metal flota-

the lab,” says Marjanovic. She says that a proper sam-

tion concentrator circuits between stages, to provide unit efficiency

pling plan needs to be established with full understand-

“Even the most accurate results from the lab would

ing of the population, including the size of the popu-

Accurate lab results are meaningless if the sampling is inappropriate

lation that the collected sample needs to represent, its heterogeneity, particle size as well as the levels of analytes of interest. The size of the gross sample needs to be calculated in such a way that the rule of every

particle having the same probability of being included in the sample applies. In practical terms (in addition to the sampling plan), this would mean proper understanding and execution of the sampling procedure in cases of manual sampling and the introduction of semi-automated/ automated sampling. It has been shown that the most representative sample can be taken from the “moving” sample, as found on the conveyer belt, etc. Spectro’s range of three models includes analytical instruments for routine analysis of relevant elements, from sodium to uranium, to determine minor and trace elements, as well as field investigations and surveys. According to the author, EDXRF technology and calibration technology are employed in their instruments to minimise and compensate for matrix effects.

In sid e M in in g 0 4 | 2 0 1 6

events

Quashing perceptions At the 7th Annual Women in Mining Conference held in February this year, a group of women employed in the South African mining industry gathered at the Indaba Hotel to address topical issues affecting the fairer sex in the old boys’ club that is mining.

he well-attended conference

the negative views that female board

work for long periods as a result. Key

saw known and respected females

members and executives lacked the

principles she highlighted:

cover topics across the board, in-

necessary skills and knowledge to effec-

• dignity for women

cluding the use of the Mining Char-

tively run mining operations.

• cultural inclusion

ter as a tool to progress women in mining.

• respect

Topics covered included the compliance

Rife prejudice

of the amended LRA while simultaneously

“These attitudes by male executives and

She indicated that all of the aforemen-

advancing women. The consensus at

mineworkers have resulted in women

tioned points were key priorities to De

the conference was that women in the

themselves questioning whether they are

Beers’ 2016 transformation model.

mining industry have indeed made great

good enough. This is an unacceptable

strides over the past decade.

and untenable position for women,”

tendance, agreed that the mining indus-

Zikalala reaffirmed.

try was still mostly an “all-boys’ club” at

But, in the same breath, a significant amount of work still needs to be done to

• promotion of cultural diversity.

Both women, and many others in at-

Zikalala’s colleague, Varsha Morar,

the board and executive levels, with the

see women achieve and succeed, at

lead: Organisational Effectiveness, De

fairer sex making up less than 25% of posi-

boardroom level, to the same extent as

Beers, expressed how an aggressive cul-

tions at senior management levels.

their male counterparts. Like last year, the

tural shift was needed at organisational

conference featured Nompumelelo Zikal-

level by the mining companies them-

icant take-home point from the Women

ala, general manager, De Beers. Ever a

selves, to ensure the inclusion of women

in Mining Conference was there is still a

pillar of inspiration, Zikalala addressed the

at all levels. Morar asserted that there

large amount of work to put in in a bid to

perception that women who reach senior

were more than enough capable wom-

equalise opportunities between men and

leadership positions in the mining indus-

en often sidelined for promotions owing

women in the industry. But, all is not doom

try did so by “offering sexual favours” to

to the concern that they were weak or

and gloom; change has been noted and

male executives. Zikalala condemned

would fall pregnant and be absent from

the outlook remains encouraging.

Sandvik Mining Systems

Among many outcomes, the most signif-

index to advertisers

13th Annual Top Women Awards

DRC Mining Week

2016 Junior Mining Indaba

Energyst

AEL Mining Services

IFC

Joy Global

16 7 OBC

A-OSH Expo

Kansai Plascon

Dosetech

Minopex

Ins i de Mi n i n g 0 4 | 2 0 1 6

Sapics

2 27

Tega Industries

ThyssenKrupp

IBC

Winches & Winders WorleyParsons

30 9