The geochemistry of agate and chalcedony in volcanic rocks represents an intricate record of silica precipitation and crystallisation processes occurring under variable thermal and chemical conditions ...

Chalcedony includes minerals like agate, onyx, jasper, and heliotrope. Chalcedony has a waxy lustre and is usually translucent to opaque. Key characteristics of Chalcedony include its hardness (around ...

Thundereggs look like regular rocks from the outside, but contain intricate and colorful mineral patterns inside — often made of quartz, chalcedony, or agate. They are nodule-like rocks typically ...

L-23 (Little Colorado River Gravel Chert, Petrified Wood, Agate, Chalcedony): Not a direct collection from outcrop; Provenience includes samples from gravel deposits; Collection includes raw material, ...

For Chinese people, agate symbolizes longevity and is said to elevate the mood, giving people confidence. In traditional Chinese medicine it was used to treat eye ailments by placing it on the eye ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. NMNH - Anthropology Dept.