Difference between revisions of "Chalcedony"

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Chalcedony is microcrystalline (cryptocrystalline) [[quartz]]. The word is often used to encompass all varieties of microcrystalline quartz such as jasper, carnelian, chrysoprase and bloodstone. The mineral is very abundant and found all over the world.The most common variety is a muted blue-gray tone (unnamed) found in geodes and vugs.

Revision as of 12:56, 2 October 2006

Chalcedony
Chemical composition Silicon dioxide SiO2
Crystal system Trigonal
Habit Aggregate
Fracture Conchoidal
Hardness 6.5-7
Refractive index 1.535 - 1.539
Specific gravity 2.60
Lustre Vitreous

Chalcedony is microcrystalline (cryptocrystalline) quartz. The word is often used to encompass all varieties of microcrystalline quartz such as jasper, carnelian, chrysoprase and bloodstone. The mineral is very abundant and found all over the world.The most common variety is a muted blue-gray tone (unnamed) found in geodes and vugs.