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
Mineral GroupSilicates
Usesjewelry, ornamental, collector
Associated Mineralscalcite, goethite, hematite
Raritycommon
Description
A large cluster of vibrant purple quartz crystals, forming a geode-like structure with well-formed crystal terminations. The crystals exhibit a translucent quality, allowing light to pass through.
Geological Context
Amethyst typically forms in hydrothermal veins and cavities within igneous rocks, particularly basaltic lavas, where silica-rich fluids deposit quartz over time. The purple color is attributed to irradiation and iron impurities within the quartz lattice.
