Quartz
Species
Common · SiO₂
One of the most abundant minerals in Earth's crust. Forms in a wide range of geological environments, from granite pegmatites to hydrothermal veins and sandstones. Being piezoelectric, a cut crystal vibrates at a precise frequency in an alternating electric field, which is why it keeps time in clocks and radios.
Identity
- Formula
- SiO₂
- Chemical class
- Silicate
- Varieties
- Amethyst, Chalcedony, Citrine, Rose Quartz, Smoky Quartz, Tiger's Eye
- Mineral group
- Agate, Bloodstone, Carnelian, Jasper, Moss Agate, Onyx
- Also known as
- Rock crystal (colourless variety), Kristallos (ancient Greek)
- Used in alchemy
- Crystal Powder, Quartz Powder
Crystallography
- Crystal system
- Trigonal
- Habits
- Prismatic, Massive, Drusy
- Fracture
- Conchoidal
Physical properties
- Mohs hardness
- 7
- Density
- 2.65 g/cm³
- Luster
- Vitreous
- Colors
- colorless, white, purple, pink, yellow, brown, black
- Streak
- white
- Transparency
- Transparent, Translucent, Opaque
Geology
- Origins
- Hydrothermal, Metamorphic, Sedimentary, Igneous
- Host rocks
- Granite, Schist and gneiss, Sandstone, shale and clay
- Associated minerals
- feldspar, Mica, Calcite, Fluorite, Chlorite, Epidote
- Found in
- Banded iron formation, Conglomerate, Flint, Gneiss, Granite, Laterite, Mudstone, Pegmatite, Quartzite, Rhyolite, Sandstone, Schist, Shale, Slate, Banded iron formation deposit, Bog iron, Hydrothermal vein (lode), Pegmatite deposit, Porphyry copper deposit, Volcanogenic massive sulfide deposit
- Geography
- worldwide
Classification
- Rarity
- Common
- Gem quality
- Yes
Arcane properties
- Affinity
- Arcane, Light
- Effects
- Scrying, Warding
- Planar origin
- Material Plane
Sources
- M. Pasero and others, IMA Commission on New Minerals, Nomenclature and Classification, The New IMA List of Minerals, updated September 2026. International Mineralogical Association (CNMNC), 2026.
- Quartz. Mindat.org (Hudson Institute of Mineralogy).
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Quartz. Mineral Data Publishing, Handbook of Mineralogy, 2001.
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