Black Star Sapphire 12 rayed stars are not too common.

Sapphire Gemstones
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Sapphire Gemstones 14k gold heart shaped ring The Power of Royal Sapphire, King of All Blue Stones
sapphire …. naturally occurs in every color of the rainbow and in RARE cases; a type of it is known to be 1 of 5 gem species in the world with a natural color change occurrance

138.72-carat Rosser Reeves Star Ruby might be the largest and finest star ruby in the world.

This large star sapphire from Sri Lanka exhibits a rare 12-rayed star, probably caused by two sets of mineral inclusions, oriented at thirty degrees from each other. The gem is a very dark blue almost black color and weighs 70.79 carats.

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