Quartz

Quartz is one of the most abundant minerals on earth and has been used as a gemstone for as long as mankind can remember. It occurs in many forms and colors but is colorless when pure which makes it an allochromatic gemstone. In order to shed some light on the different varieties the quartz group is usually divided into two: the monocrystalline varieties and the polycrystalline varieties. To find out more about a specific member of the quartz group click on its name or image:</.p>

Monocrystalline Quartz
Polycrystalline Quartz
Amethyst.jpg
Amethyst
Agate.jpg
Agate
Ametrine.jpg
Ametrine
Carnelian.jpg
Carnelian
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Citrine
Chrysoprase.jpg
Chrysoprase
Rock Crystal.jpg
Rock Crystal
Jasper.jpg
Jasper
Smokey.jpg
Smoky Quartz
Onyx.jpg
Onyx
Rose3.jpg
Rose Quartz
Great Cameo of France.jpg
Sardonyx
Prasiolite
Bloodstone4.jpg
Bloodstone
Aventurine
Tigereye.jpg
Tiger's-Eye
Gemological information for Quartz
Color All colors
Crystal Structure Trigonal
Refractive Index 1.544-1.553
Durability Very durable
Hardness 7
Treatments May be irradiated and heat treated, depending on variety
Country of origin Worldwide deposits
Quartz care
Ultrasonic cleaning Usually safe
Steam cleaning Usually safe
Warm soapy water Safe
Chemical attack Avoid
Light sensitivity May fade
Heat sensitivity May change color

Online G&G articles on quartz