Article · Wikipedia archive · Last revised Jun 24, 2026

Anyolite

Anyolite is a metamorphic rock composed of intergrown green zoisite, black/dark green pargasite and ruby. It has been found in the Arusha Region of Tanzania and in Austria. It is sometimes incorrectly advertised as a variety of the mineral zoisite. The term anyolite is, however, not an officially accepted term for a metamorphic rock. Its name derives from the Maasai word anyoli, meaning "green". Anyolite is also referred to as ruby in zoisite, ruby zoisite, ruby-zoisite or Tanganyika artstone.

Last revised
Jun 24, 2026
Read time
≈ 1 min
Length
288 w
Citations
7
Source
Anyolite from Mundarara Mine, Tanzania. Red colored ruby inclusions are visible. source ↗

Anyolite is a metamorphic rock composed of intergrown green zoisite, black/dark green pargasite and ruby.1 It has been found in the Arusha Region of Tanzania and in Austria.1 It is sometimes incorrectly advertised as a variety of the mineral zoisite. The term anyolite is, however, not an officially accepted term for a metamorphic rock.2 Its name derives from the Maasai word anyoli, meaning "green".1 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, 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 £100,3 although it was eventually sold for £8000.4 It is reported that the stone originally came from a mine near Arusha, Tanzania.5

Anyolite figurine source ↗
References

References

  1. http://www.mindat.org/min-27151.html Mindat
  2. Metamorphic rocks, A classification and glossary of terms, D. Fettes and J. Desmons ed., Cambridge University Press
  3. Jonathan Guthrie (October 1, 2009). "Now £11m Gem of Tanzania hits rock bottom". Financial Times. Archived from the original on 2022-12-10.
  4. "Wrekin's '£11m' Gem of Tanzania ruby sold for £8k". BBC News. 16 February 2010.
  5. Guthrie, Jonathan; Pearson, Samantha (27 March 2019). "The strange journey of the 'jinxed' jewel". Financial Times. Archived from the original on 2022-12-10. Retrieved 18 September 2019.
External links