Varieties (according to microstructure)




Although many of the varietal names historically arose from the color of the mineral, current scientific naming schemes refer primarily to the microstructure of the mineral. Color is a secondary identifier for the cryptocrystalline minerals, although it is a primary identifier for the macrocrystalline varieties.

Major varieties of quartz
Type Color & Description Transparent
Herkimer diamond Colorless Transparent
Rock crystal Colorless Transparent
Amethyst Purple to violet colored quartz Transparent
Citrine Yellow quartz ranging to reddish orange or brown, and occasionally greenish yellow Transparent
Ametrine A mix of amethyst and citrine with hues of purple/violet and yellow or orange/brown Transparent
Rose quartz Pink, may display diasterism Transparent
Chalcedony Fibrous, variously translucent, cryptocrystalline quartz occurring in many varieties.
The term is often used for white, cloudy, or lightly colored material intergrown with moganite.
Otherwise more specific names are used.
Carnelian Reddish orange chalcedony Translucent
Aventurine Quartz with tiny aligned inclusions (usually mica) that shimmer with aventurescence Translucent to opaque
Agate Multi-colored, curved or concentric banded chalcedony (cf. Onyx) Semi-translucent to translucent
Onyx Multi-colored, straight banded chalcedony or chert (cf. Agate) Semi-translucent to opaque
Jasper Opaque cryptocrystalline quartz, typically red to brown but often used for other colors Opaque
Milky quartz White, may display diasterism Translucent to opaque
Smoky quartz Light to dark gray, sometimes with a brownish hue Translucent to opaque
Tiger's eye Fibrous gold, red-brown or bluish colored chalcedony, exhibiting chatoyancy.
Prasiolite Mint green Transparent
Rutilated quartz Contains acicular (needle-like) inclusions of rutile
Dumortierite quartz Contains large amounts of dumortierite crystals Blue

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