Where am I? >
Gallery view selector
Chalcedony — specimen 0685, photo © NMNHS
no precise locality [Africa]
7.94 | 6.91 | 4.96 mm;
Clean specimen; design ‘Hexamixtum S 41-32’ [pavilion angle changed to 45.00], excellent cut by Tan Pen.
More information from ‘Classification’
Traditionally defined as a fibrous cryptocrystalline variety of quartz. More recently, it has been shown that much chalcedony is a mixture of quartz and
. Pure chalcedony may contain trace amounts of
Gemmology — gemstones
National Museum of Natural History, Sofia
Use of this website assumes acceptance of our
. For contacts:
None of the specimens illustrated in this site is on display in the permanent exhibition of the National Museum of Natural History, Sofia.