Quartz
Image: Georges Jansoone (CC BY 2.5)
Mineral NameQuartz
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorscolorless, smoky brown
Transparencytransparent
Type LocalityWidespread globally in various geological settings; common in pegmatites and hydrothermal veins.
Mineral GroupSilicates
Usesjewelry, industrial, collector specimens
Associated Mineralsfeldspar, mica, tourmaline, calcite
Raritycommon
Description
A large, well-formed, transparent to smoky brown hexagonal crystal with prominent pyramidal terminations, displaying a bright vitreous luster.
Geological Context
Quartz is a ubiquitous mineral, forming in igneous rocks (like granite and pegmatites), metamorphic rocks (like gneiss and schist), and sedimentary rocks (as sand and chert), often crystallizing from hydrothermal solutions.
