This Art Deco platinum bow brooch (ca. 1930) features 16 rectangular and trapezoidal faceted black onyxes and 46 round, old European-cut diamonds. Photo courtesy of liveauctioneers.com and Quinn's Auction Galleries - Central Virginia.
Opaque Black Chalcedony Faceted in Brooch
This Art Deco platinum bow brooch (ca. 1930) features 16 rectangular and trapezoidal faceted black onyxes and 46 round, old European-cut diamonds. Photo courtesy of liveauctioneers.com and Quinn's Auction Galleries - Central Virginia.
Article: Onyx Properties, Varieties, and Jewelry Information
Credit: Quinn’s Auction Galleries – Central Virginia
| Gemstone | Quartz, Chalcedony, Onyx |
| Natural or man made | Natural |
| Jewelry type | Brooch |
| Gem State | Faceted |
| Color | Black |
| Transparency | Opaque |