Although anyolite is advertised as a variety of the mineral zoisite of Tanzania , anyolite is actually a metamorphic rock composed of intergrown green zoisite, black/dark green pargasite (erroneously identified as tschermakite 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, ruby zoisite, ruby-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, 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