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13.30 carat Koroit Boulder 16mm Square opal blue green fire pattern, Australian loose gemstone - Eo-441


Beautiful 16mm square boulder opal with a strip of green and blue fire running down the centre.  Will make a great pendant or large ring stone.


Mine - Koroit Boulder
Body Tone - Iron Stone
Brightness - 3/5
Fire colour - Green and blue
Size - 16x16x5mm
Weight - 13.30 carat


Price is for the stone pictured


About Opals from around the world - 


Treatment: Natural

Colours Opal Can Be: Black, White, Blue, Green, Red, Yellow, Pink, Grey, Purple, Orange, Brown

Luster: Pearly, Vitreous, Opalescence

Birthstone zodiac sign: Libra

Associated month: October

Crystal system: Amorphous solid

Chemical formula: SiO₂·nH₂O

Hardness (Mohs hardness scale): 5.5 – 6.5

Country of origin: Australia, Ethiopia, Mexico and Cornwall amazingly 

Size variations: can vary 0.3mm each way on all dimensions given.




In mystical circles, opal is considered a stone representing hope, innocence and purity. It has strong connotations of happiness, faithfulness, loyalty and confidence.  Regarded as a powerful sea stone for safty on the water.


All orders are sent recorded delivery UK and International. 


13.3 carat Koroit Boulder Square Opal - Eo-441

SKU: Eo-441
£35.00 Regular Price
£31.50Sale Price
Only 1 left in stock
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