Terminology: soapstone, steatite, talc

Does anyone know if soapstone and steatite are the same thing?  Now in
the Conservation Terminology list, which is being produced by the Art
and Architecture Thesaurus, I have talc as a mineral with soapstone as a
metamorphic rock with a related term to talc.  Should steatite be a
synonym to soapstone or a narrower term to soapstone (that means it is a
type or variety of soapstone).  Any information or suggestions would be
greatly appreciated.

Colleen Heslip,  BM.CXH

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                  Conservation DistList Instance 5:49
                 Distributed: Wednesday, April 15, 1992
                        Message Id: cdl-5-49-002
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