Amethyst
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Mineral NameAmethyst
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorspurple, violet
Transparencytransparent
Type LocalityBrazil, Uruguay, Zambia, Russia
Mineral GroupSilicates
Usesjewelry, ornamental, collector
Associated Mineralsquartz, feldspar, calcite
Raritycommon
Description
Amethyst is a purple variety of quartz, often found as prismatic crystals or lining geodes. Its distinctive color ranges from pale lilac to deep violet.
Geological Context
It typically forms in hydrothermal veins and cavities within igneous rocks, particularly basaltic lavas, where silica-rich fluids deposit the quartz crystals.
