Gemmology
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Chalcedony — specimen 0088, photo © NMNHS
Chalcedony — specimen 0088, photo © NMNHS

Chalcedonyspecimen 0088

Origin

South America
Brazil
Chalcedony — specimen 0088, locality map
Data

Weight: 1.80 ct; size: 9.14 | 7.13 | 4.66 mm; shape: oval; colour: medium very strongly bluish green; slightly greyish; clarity: translucent; cut: fair; treatment: none.
Notes

Clean specimen; mixed style cut.

Other specimens
Chalcedony — specimen 0403Chalcedony — specimen 0180Chalcedony — specimen 0510Chalcedony — specimen 0511Chalcedony — specimen 0512Chalcedony — specimen 0580Chalcedony — specimen 0591Chalcedony — specimen 0225Chalcedony — specimen 0688Chalcedony — specimen 0418Chalcedony — specimen 0558Chalcedony — specimen 0179Chalcedony — specimen 0183Chalcedony — specimen 0404Chalcedony — specimen 0265Chalcedony — specimen 0348Chalcedony — specimen 0684Chalcedony — specimen 0685

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 mogánite. Pure chalcedony may contain trace amounts of silanol groups.