Dear Amit Mandal,
There are a wide variety of opaque minerals in carbonatites.
Magnetite is probably the most common, especially in calcite carbonatite,
and often forms attractive octahedra. Hematite and goethite are present in
altered calcite, dolomite, and ankerite carbonatites.
Sulphides, such as pyrrhotite, pyrite, and chalcopyrite are also common.
Sphalerite occurs in late-stage ankerite carbonatite as does galena. A
whole range of other sulphides have also been described, including
jamesonite, boulangerite, tetrahedrite, bornite... For a slightly dated but
nevertheless less useful summary, see the book, Mineralogy of Carbonatites
by Yu. L. Kapustin, published in English translation in 1980 by Amerind
Publishing, New Dehli, 259pp.
A suite of exotic Pt group minerals have been described recently from
phoscorites-carbonatites at Phalabowra, S.Africa and Kovdor, Russia
by Rudashevsky et al. I can give you references for these papers if you are
interested.
Hope this is useful,
Best wishes,
Frances Wall
At 21:14 30/03/00 +0530, you wrote:
>dear all, i want to know about the opaque minerals present in the
>carbonatite. I am working on carbonatite.
>
> amit mandal.
>
>
>
Frances Wall
Department of Mineralogy
The Natural History Museum
Cromwell Road
London, UK
SW7 5BD
Tel: +44 (0)20 7 942 5623
Fax: +44 (O)20 7 942 5537
Email: [log in to unmask]
http://www.nhm.ac.uk/science/
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