THIS IS A HEATED VERY DARK BLUE MONTANA SAPPHIRE AT 1.59 CARATS. THIS STONE HAS BEEN HEATED ONLY, TO ENHANCE THE COLOR AND IT VERY WELL DID JUST THAT. IT STILL HAS INCLUSIONS BUT WOULD MAKE A NICE NECKLACE OR RING. SOME OF THE INNER INCLUSIONS REFRACT MINIATURE RAINBOW SHARDS. VERY INTERESTING.