LUSTER sierra hughes
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Tourmaline The color of some Tourmaline can be enhanced through heat treatment. Tourmalines’ color may actually be different when viewed at different angles. If a specimen is put under a pressure or temperature change, it will generate an electrical charge.
Tourmaline is a group of several closely related minerals. The three most wellknown members are Elbaite, Schorl, and Dravite. It is the most multicolored mineral type known, occurring in virtually every color of the spectrum. Individual stones are often multicolored and are unsurpassed in their beauty.
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Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
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Rhodochrosite Rhodochrosite’s red and hot pink crystals are extremely sought after and good crystals. Rhodochrosite belongs to the calcite group. All members of the calcite group crystallize in the trigonal system, have perfect rhombohedral cleavage, and exhibit strong double refraction. When Rhodochrosite is exposed to the atmosphere, it may develop a thin film of manganese oxide on its surface. This may slightly darken the color of a specimen.
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MnCO3
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Amazonite
There are no Amazonite deposits that exist in the Amazon region, so presumably this stone is named to its resemblance in color to the green of the tropical rainforest.
Amazonite is a translucent to opaque feldspar gemstone with a pretty green color. It is the greenish variety of the mineral Microcline. Amazonite is named after the Amazon River of South America.
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KAlSi3O8
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Fluorite Pure Fluorite is colorless; the color variations are caused by various impurities. Some colors are deeply colored, and are especially pretty in large well-formed crystals, which Fluorite often forms. Sometimes coloring is caused by hydrocarbons, which can be removed from a specimen by heating. Fluorite is one of the more famous fluorescent minerals. In fact, the word “fluorescent� is derived from the mineral Fluorite. The name of the element fluorine is also derived from Fluorite, as Fluorite is by far the most common and well-known fluorine mineral.
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CaF2
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Calcite exhibit strong double refraction in transparent rhombohedrons. Calcite may form as an undesirable coating on top of another mineral. The calcite can be easily burned off by soaking it in acid, which will cause it to effervesce and eventually dissolve, leaving the mineral below exposed.
Calcite is the one of the most common minerals on earth. It occurs in a seemingly unlimited variety of shapes and colors. It constitutes a major portion of many of the earth’s rocks. All members of the calcite group crystallize in the trigonal system, have perfect rhombohedral cleavage, and
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CaCO3
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SIERRA HUGHES Design Technology ‘15 Look Book