mineral
Quartz
Silicon Dioxide (SiO2)
Hardness of 7 on the Mohs scale. Color ranges from colorless (rock crystal) to white, milky, gray, pink, or smoky. Vitreous (glassy) luster. Crystal structure is trigonal. Conchoidal fracture with no true cleavage. Specific gravity is approximately 2.65.
Identified More mineral →
Explore Quartz in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 7 on the Mohs scale. Color ranges from colorless (rock crystal) to white, milky, gray, pink, or smoky. Vitreous (glassy) luster. Crystal structure is trigonal. Conchoidal fracture with no true cleavage. Specific gravity is approximately 2.65.
Formation & geological history
Forms in a wide variety of geological environments, most notably in igneous, metamorphic, and sedimentary rocks. It crystallizes from silica-rich hydrothermal solutions or magma and is very resistant to weathering.
Uses & applications
Used extensively in electronics, glassmaking, abrasives, gemstones, and construction materials.
Geological facts
Quartz is one of the most abundant minerals found in the Earth's continental crust. Its piezoelectric properties make it essential for keeping accurate time in watches and clocks.
Field identification & locations
Easily identifiable in the field by its high hardness (scratches glass), conchoidal fracture, and lack of cleavage. Found worldwide in nearly every geological setting.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
sedimentary
Limonite / Goethite (Iron Ore Mineral nodule)
FeO(OH)·nH2O / FeO(OH)
mineral
Septarian Pebble
Septarian nodule / Concretion
sedimentary
Schist
Schist
Metamorphic
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral