Quartz (Rock crystal)
Image: <a href="//commons.wikimedia.org/wiki/User:Kulmalukko" title="User:Kulmalukko">Tiia Monto</a> (CC BY-SA 3.0)
Mineral NameQuartz (Rock crystal)
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorscolorless, white
Transparencytransparent
Type LocalityDauphine, France
Mineral GroupSilicates
Usesjewelry, industrial, collector, oscillators
Associated Mineralsfeldspar, mica, calcite, pyrite
Raritycommon
Description
A large, transparent, colorless hexagonal crystal of quartz, exhibiting well-formed terminations, mounted on a light-colored matrix.
Geological Context
Quartz is a ubiquitous mineral found in igneous, metamorphic, and sedimentary rocks, forming from the crystallization of silica-rich magmas or hydrothermal solutions, or through diagenesis in sediments.
