gr 68 b6 This sapphire is from the Umba valley Tanzania parcel we brought many years ago. the cut is highly unorthodox & i chose to cut it this way to enhance the blue. official people from the gemological association of Australia would criticize me for this but the blue color is so heart breaking i dont care. being a sapphire even though it has a high crown it will tolerate the knocks it will get if set in a ring, & to have this tone of blue is worth any difficulty. this is a totally natural stone, and apart from using my skills as a cutter to enhance the color there has been no other treatments.