Locality: Merelani Hills, near Arusha, Umba Valley, Tanzania. Size Class: Miniature. Collection: Private. Tanzanite (gem zoisite) gem crystals should show very good blue and purple (and sometimes red/violet color when looked at through the bottom) in their natural form. This is an unheated (untreated) and natural tanzanite crystal showing superb purple and blue hues, 23 grams in mass. It has excellent blue color and displays its gemminess without the need for backlighting. A custom lucite display base is included. Size 3.5 x 2.1 x 2.1 cm.