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These gems have slight impurities that act as chromophores and give the stone its color. An example is the gem family beryl which has the base chemical formula of Be 3 Al 2 (SiO 3 ) 6 . Pure beryl will appear colorless but this rarely occurs and the presence of trace elements change its color.
Topaz is a silicate mineral made of aluminum and fluorine with the chemical formula Al 2 Si O 4 (F, OH) 2.It is used as a gemstone in jewelry and other adornments. Common topaz in its natural state is colorless, though trace element impurities can make it pale blue or golden brown to yellow-orange. [7]
Other chemical impurities may include calcium, sodium, and potassium. Gedrite also forms a series with another ferromagnesian amphibole, anthophyllite . Gedrite occurs in contact and medium to high grade metamorphic rocks in association with garnet , cordierite , anthophyllite , cummingtonite , sapphirine , sillimanite , kyanite , quartz ...
Llanite Llanite from the dike on Texas State Highway 16. Llanite is a porphyritic rhyolite with distinctive phenocrysts of blue quartz (a rare quartz color) and perthitic feldspar (light grayish-orangeish). The brown, fine-grained groundmass consists of very small quartz, feldspar, and biotite mica crystals.
Sylvite is found in many evaporite deposits worldwide. Massive bedded deposits occur in New Mexico and western Texas, and in Utah in the US, but the largest world source is in Saskatchewan, Canada. The vast deposits in Saskatchewan were formed by the evaporation of a Devonian seaway. Sylvite is the official mineral of Saskatchewan.
Diamonds are separated into five types: Type IaA, Type IaB, Type Ib, Type IIa, and Type IIb. The impurities measured are at the atomic level within the crystal lattice of carbon atoms and so, unlike inclusions, require an infrared spectrometer to detect. [1] Different diamond types react in different ways to diamond enhancement techniques.
The heaviest hail stone on record in the United States had a reported diameter of 11 inches (27.94 centimeters) and weighed nearly 2 pounds (907 grams). It was discovered near Vivian, South Dakota ...
Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, [1] [2] is an opaque, [3] impure variety of silica, usually red, yellow, brown or green in color; and rarely blue.