Dear Dr Mishra,
A complete solid-solution series exists between jamesonite
[4PbS-FeS-3Sb2S3] and [4PbS-MnS-3Sb2S3]. Benevidesite, although not
originally characterised as the end member of this series represents
'manganoan jamesonite' where the Mn:Fe ratio is between 62:38 to 73:27.
Chang et al (1987) Can. Min. 25, 667-672 worked on the synthetic phase
relationships, determined the existence of a s-s series and named
benevidesite as the end member i.e. Mn:Fe ratio 51:49 to Mn:Fe 100:0.
I hope this is of some use to you.
Regards
Chris Stanley
,./
At 19:02 11/03/01 +0530, you wrote:
>Dear all:
>
>Can anyone educate me on manganoan jamesonite, in relation to phase
>relation (stability) and natural occurrences.Also I shall appreciate help
>in relation to some references on ullmanite-gudmundite association. Thanks
>in advance and cheers,
>B. Mishra
>
>
>---------------------------------------------
>Dr.B Mishra, Associate Professor
>Department of Geology & Geophysics
>Indian Institute of Technology
>Kharagpur WB 721 302 India
>Tel: +91-03222-83372(O)/83373(R)/78194(R)
>Fax: +91-03222-82268/55303
>e-mail: [log in to unmask]
>-----------------------------------------------
>
>
Chris J Stanley BSc PhD MIMM CGeol F.Min.Soc. FGS,
Deputy Head of Department of Mineralogy
Natural History Museum, Cromwell Road, LONDON SW7 5BD,UK
Tel. +44 (0)20 7942 5627 Fax. +44 (0)20 7942 5537
Museum web site at: http://www.nhm.ac.uk
Personal Web site at: http://www.nhm.ac.uk/mineralogy/stanley/stanley.htm
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