mineral
Likely smoky quartz crystal
Quartz (SiO₂), possibly smoky quartz
AI-generated identification · may be incorrectSmall, translucent brown-gray crystal with a vitreous luster and apparent pointed termination. Quartz has Mohs hardness 7, a trigonal crystal structure, no cleavage, and conchoidal fracture; the photo is insufficient to confirm the identification.
Identified More mineral →
Explore Likely smoky quartz crystal in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Small, translucent brown-gray crystal with a vitreous luster and apparent pointed termination. Quartz has Mohs hardness 7, a trigonal crystal structure, no cleavage, and conchoidal fracture; the photo is insufficient to confirm the identification.
Formation & geological history
Quartz crystallizes from silica-rich fluids in cavities and veins, commonly in granites and pegmatites; its age depends on the host deposit.
Uses & applications
Quartz is used in jewelry, decorative specimens, glassmaking, and electronics; this small piece is chiefly a pocket or beginner-collection specimen.
Geological facts
Smoky coloration commonly results from radiation-induced defects associated with trace aluminum in the quartz crystal.
Field identification & locations
Check for glassy luster, hardness near 7, and lack of cleavage; crystal faces and termination can help distinguish natural quartz from chips of other minerals. Quartz occurs worldwide, including Brazil, the United States, and the Alps.
More like this
Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Tumbled granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous