Amethyst
Image: Zopilote0 (CC BY 2.0)
Mineral NameAmethyst
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorspurple, violet, lavender
Transparencytransparent
Type LocalityWorldwide (e.g., Brazil, Uruguay, Zambia, Russia)
Mineral GroupSilicates
Usesjewelry, collector, ornamental
Associated Mineralsquartz, calcite, goethite, hematite
Raritycommon
Description
This specimen displays a cluster of vibrant purple to lavender amethyst crystals, some with a vitreous luster, embedded within a lighter, possibly altered or earthy matrix. The crystals show varying shades of purple, characteristic of this quartz variety.
Geological Context
Amethyst typically forms in hydrothermal veins and cavities within igneous rocks, such as basaltic lava flows, or in metamorphic rocks. Its distinctive purple color results from trace iron impurities within the quartz structure, which are then exposed to natural irradiation.
