Sapphire has a hardness of 9 on the Mohs scale. This beautiful piece of Sapphire from The Umba Valley in Tanzania weighs 3.58cts, measures 8x6x4mm and has some small viels.UMBA SAPPHIRE 3.58 CTS 8X6X4MMSKU: UMSA#15 $720.00 Regular Price$216.00Sale PriceQuantityAdd to CartBuy Now