Alexandrite are very rare gemstones and luckily, they are also very durable. With a Mohs rating of 8.5, they are just under corundum and diamond in hardness. The value of Alexandrite's seems durable too, as these tantalizing gemstones remain in very short supply. This natural, untreated alexandrite is very eye clean and came from Tanzania. It has no color zoning and changes from a delicate yellowish green in daylight to red-purplish brown in incandescent lighting. The popular round shape was achieved with a brilliant/step cut and brings out the sparkle of this loose gemstone. Given their durability and uncommon beauty, you will want to wear your exotic alexandrite every day!