What is Glass?

What is glass? Scientists tell us that glass is a state of matter rather than a single material. It is formed when a molten material cools so rapidly that there is not enough time for the material’s crystalline structure to re-form. Solids have atoms and molecules arranged in perfectly ordered, lattice-like structures. In liquids and gases, atoms and molecules are free to move about in a random way, which is why they can flow. In glass, the atoms and molecules are held rigidly in place so that they cannot flow.

A brief history of glass Natural glass

Did you realise that glass can be found in nature? It can be the result of a variety of events. Glass can form pretty much anywhere, however extreme temperatures are required in order to create the perfect natural conditions to produce glass. Volcanoes spewing molten rock, lightning striking sand and meteorites falling from the sky can all cause the right environmental conditions for glass to form.

Origins of glass making

While glass may always have been found naturally, the first instance of man-made glass may be traced back about 4000BC in both Mesopotamia and Egypt. Archaeologists have found glass covered stone beads from this time. Glass blowing is thought to have begun around 50BC and attributed to Phoenicians (Lebanon and Jordan region). By the First Century BC, glass blowing was becoming popular across Europe and the Middle East courtesy of the Roman Empire. The Romans were talented glass makers and were the first to use glass in architecture.

Throughout the years, the use of glass has evolved and developed to serve many different purposes. In the Middle Ages, coloured sheet glass developed and became popular in churches to create stain glass windows. During the Renaissance, glass making and glass artistry was particularly popular in Italy. The island of Murano in Italy rose to fame for the strong glass making industry that developed there and still thrives today.

Over time, glass making techniques and mastery made their way across Europe and a number of key advances were made. These advances included the invention of lead crystal glass and the refinement of raw materials used in the glass making process to make clear glass. This refinement reduced the amount of clouding which was prevalent in glass.

These developments were critical in the adoption of glass as a material used in functional objects. The glass was now softer and easier to decorate and had a higher refractive index, adding to its brilliance and beauty, and it proved invaluable to the optical industry. Inventions such as optical lenses, astronomical telescopes and microscopes became possible with these developments.

Since this time, huge advances in glass and glass making have occurred and glass is widely accepted as a material for building, medical tools, common household items and artworks.