Home >> Contributions to Mineralogy and Petrology, Volume 148, Number 3

Kokchetavite: a new potassium-feldspar polymorph from the Kokchetav ultrahigh-pressure terrane

Authors: Hwang, Shyh-Lung1; Shen, Pouyan2; Chu, Hao-Tsu3; Yui, Tzen-Fu4; Liou, Juhn5; Sobolev, Nikolay6; Zhang, Ru-Yuan5; Shatsky, Vladislav6; Zayachkovsky, Anton7

Source: Contributions to Mineralogy and Petrology, Volume 148, Number 3, November 2004 , pp. 380-389(10)

Publisher: Springer

Buy & download fulltext article:

OR

Price: $47.00 plus tax (Refund Policy)

Abstract:

Kokchetavite, a new polymorph of K-feldspar (KAlSi3O8), has been identified as micrometer-size inclusions in clinopyroxene and garnet in a garnet-pyroxene rock from the Kokchetav ultrahigh-pressure terrane, Kazakhstan. Kokchetavite has a hexagonal structure with a =5.27(1) Å, c=7.82(1) Å, V=188.09 Å3, Z=1, and is found to be associated with phengite + α/β-cristobalite (or quartz) + siliceous glass ± phlogopite/titanite/calcite/zircon, occurring as multi-phase inclusions in clinopyroxene and garnet. It is concluded that kokchetavite could not be an exsolution phase in host minerals. Instead, it might be metastably precipitated from an infiltrated K-rich melt during rock exhumation. Alternatively, although less likely, kokchetavite might be derived from dehydration of K-cymrite, which, in turn, was formed at high pressures. In either case, kokchetavite is a metastable polymorph of K-feldspar.

Document Type: Research article

DOI: http://dx.doi.org/10.1007/s00410-004-0610-2

Affiliations: 1: Department of Materials Science and Engineering, National Dong Hwa University, Hualien, Taiwan, ROC, Email: slhwang@mail.ndhu.edu.tw 2: Institute of Materials Science and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan, ROC, 3: Central Geological Survey, P.O. Box 968, Taipei, Taiwan, ROC, 4: Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, ROC, 5: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA, 94305, USA, 6: Institute of Mineralogy and Petrography, Siberian Branch of Russian Academy of Sciences, 630090, Novosibirsk, Russia, 7: NEDRA Geological Expedition, 475013, Kokchetav, Kazakhstan,

Publication date: 2004-11-01

Marked list

Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content

Text size:

A | A | A | A
^ Back to top
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages. print icon Print this page