Anyolite

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.[1][2] The term anyolite is however not an officially accepted term for a metamorphic rock.[3] 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.

Anyolite
General
CategoryMineral
Identification
ColorGreen with ruby inclusions and black spots
Crystal habitMassive
Mohs scale hardness6-7
Specific gravity3.2-3.5

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,[4] although it was eventually sold for £8000.[5] It is reported that the stone originally came from a mine near Arusha, Tanzania[6]

References
  1. http://www.mindat.org/min-27151.html Mindat
  2. http://www.cst.cmich.edu/users/dietr1rv/zoisite.htm Gemrocks
  3. Metamorphic rocks, A classification and glossary of terms, D. Fettes and J. Desmons ed., Cambridge University Press
  4. Jonathan Guthrie (October 1, 2009). "Now £11m Gem of Tanzania hits rock bottom". Financial Times.
  5. "Wrekin's '£11m' Gem of Tanzania ruby sold for £8k". BBC News. 16 February 2010.
  6. Guthrie, Jonathan; Pearson, Samantha (27 March 2019). "The strange journey of the 'jinxed' jewel". Financial Times. Retrieved 18 September 2019.


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