Pietersite

Pietersite is a commercial term for a variety of the mineral Chalcedony. Originating from Namibia and China, where it is mined for use as a decorative stone due to its chaotic chatoyancy and brecciated structure.

Polished Pietersite

Ranging in colour from brownish-red, to blue-grey, and chatoyant yellow. The Chinese variety are predominantly a reddish-brown, with regions of chatoyant blue and yellow. The Namibian variety are less varied, being predominantly a chatoyant blue-grey, with less common reddish-browns and yellows.[1]

It was first described in Namibia in 1962[2] and was discovered in Xichuan - in the Henan Province of China - in 1966.[3]

Often inaccurately described as a brecciated form of Tiger's-Eye or Hawk's-Eye, due to the brecciated texture containing chatoyant material. However, while they are similar mineralogically, Pietersite is not a brecciated form of either. Instead, the chatoyancy is due to a shared mineral, crocodolite.[1]

References

  1. Kaifan, H.; Heaney, P. (2010). "A MICROSTRUCTURAL STUDY OF PIETERSITE FROM NAMIBIA AND CHINA". Gems and Gemology. 46(n.4): 280-286. doi:10.5741/GEMS.46.4.280.
  2. Thomas, A. (2008) Gemstones: Properties, Identification and Use. New Holland Publishers, London
  3. Zhong H. (1994) Gemstone sources in Henan Province. China Lapidary, Vol. 9, No. 3, pp. 43–46

Gemdat.org

Mindat.org


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.