Choice, single, complete sphere of green Prehnite from the strange deposits in Arusha area, near where the tanzanite is mined The translucent sphere has a uniform, light green color and very good luster. There is even a small amount of overgrowth along the equator, which creates a strong resemblance to the planet Uranus. This is a simple, yet stylish, thumbnail. UNUSUAL, to say the least!