Donate now to keep alive!Help|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
What is a mineral?The most common minerals on earthMineral PhotographyThe Elements and their MineralsGeological TimeMineral Evolution
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Natural pseudowollastonite: Crystal structure, associated minerals, and geological context

Posted by Marco E. Ciriotti  
Marco E. Ciriotti February 22, 2012 10:36AM
▪ Seryotkin, Yu.V., Sokol, E.V., Kokh, S.N. (2012): Natural pseudowollastonite: Crystal structure, associated minerals, and geological context. Lithos, 134–135, 75-90.

Pseudowollastonite, an extremely rare constituent of ultrahigh-temperature combustion metamorphic and igneous rocks, has been found as a rock-forming mineral in Ca-rich paralava veins of Nabi Musa fossil mud volcano (Dead Sea area). Pseudowollastonite-bearing paralavas are the products of combustion metamorphism associated with spontaneous burning of methane. The melt began to crystallize at 1480–1500 °C about the ambient pressure. Pseudowollastonite enters two mineral assemblages: (1) rankinite, larnite, nagelschmidtite, wollastonite (1T), gehlenite-rich melilite, Ti-rich andradite, cuspidine, and fluorapatite; (2) parawollastonite (2M), wollastonite (1T), gehlenite-rich melilite, Ti-rich andradite, fluorellestadite. In this study we present the first single-crystal structure determination of natural pseudowollastonite. Pseudowollastonite from Nabi Musa dome is stoichiometric CaSiO3 and belongs to the most widespread four-layer polytype: a = 6.83556(10) Å, b = 11.86962(18) Å, c = 19.6255(3) Å, β = 90.6805(13)°, V = 1592.21(4) Å3, space group C2/c. We argue that pseudowollastonite is so scarce in nature because its formation requires joint action of several uncommon factors: availability of hot melts of T > 1200 °C that bear free calcium but are poor in Mg and Fe (mostly as Fe3+) and their crystallization in the shallow crust followed by quenching.
Sorry, only registered users may post in this forum.

Click here to login

Mineral and/or Locality is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © and the Hudson Institute of Mineralogy 1993-2018, except where stated. relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: January 21, 2018 12:12:03
Go to top of page