Quartz
Image: Meralt Limited (CC BY-SA 4.0)
Mineral NameQuartz
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorscolorless, white, black, reddish-brown
Transparencytransparent
Type LocalityVakinankaratra Region, Madagascar
Mineral GroupSilicates
Usesjewelry, collector
Associated Mineralsrutile, schorl
Rarityuncommon
Description
A polished specimen of transparent to translucent quartz, prominently featuring needle-like inclusions of black and reddish-brown rutile, enhancing its visual appeal.
Geological Context
Quartz is a ubiquitous rock-forming mineral found in various geological settings including igneous, metamorphic, and sedimentary rocks. Rutilated quartz forms when rutile needles crystallize within the growing quartz crystal, typically in hydrothermal veins or pegmatites.
