Although anyolite is advertised as a variety of the mineral zoisite from Kenya and the Arusha Region of Tanzania, anyolite is actually a metamorphic rock composed of intergrown green zoisite, black/dark green pargasite (erroneously identified as tschermakite), and ruby. The term anyolite is however not an officially accepted term for a metamorphic rock. It is said to be named after the Maasai word anyoli, meaning “green.” Anyolite is also referred to as ruby in zoisite or Tanganyika artstone.
The contrasting colours make anyolite a popular material for sculptures and other decorative objects. It was first discovered at the Mundarara Mine, near Longido, Tanzania in 1954.
In 2010 it was suggested that a 2 kilogram stone known as the Gem of Tanzania owned by the defunct company Wrekin Construction and fraudulently valued at £11 million was actually a lump of Anyolite worth about £100, although it was eventually sold for £8000. It is reported that the stone originally came from a mine near Arusha, Tanzania