Gem Diopside crystals from the Tanzanite mines in Tanzania are a relatively new item on the market. They tend to be small, with the best quality ones being bright green and glassy. This piece has an excellent, rich color. It is nearly an inch long and has a smaller crystal that has joined the primary that adds character to the overall crystal. It weighs 1.7 grams (8.5 carats). An impressive article about the deposit was printed in the Mineralogical Record in September-October 2009 (the "Tanzanite Issue").