11.65ct Koroit Boulder Matrix Opal | #E202 Carnelian but not with the post

but not with the post straightened

Likely from the 1960's

The Cut: Polished Shark Tooth Shaped Cabochon Cut

post backs

11.65ct Koroit Boulder Matrix Opal | #E202 Carnelian but not with the postKoroit Boulder Matrix Opal Weight (carats) 11. 65cts Origin Koroit Mining District, Queensland, Australia Shape Freeform Dimensions (millimeters) 21. 85mm x 10. 71mm x 6. 19mm Dimensions (inches) 0. 9" x 0. 4" x 0. 25" Body Tone (+N1 to N9 ) NA Boulder Brightness ( 1 to 5+) B4 Predominant Colors Green Orange Directionality of Fire Slightly Directional Treatments Enhancements None Suggested Purpose Ring Pendant Sku Number #E202 Additional Notes None