Terminology: soapstone, steatite, talc

Geologic Novelties and Confusion
To respond to the geologic question:

Having taken geology as an undergraduate I know the hazards of defining
familiar things with certainty.  Afterall, when I was a kid, a stone was
a stone, but as a near-adult (while in college), the instructor said
that stones were not stones, they were rocks.  Since then I stood
corrected. But what has it got me?  I can say that a book repaired in
our library years ago is very similar to a metamorphic rock.  (They are
also covered with dust, although talc would accentuate the problem more
visibly to our directors.) The book has undergone change or
metamorphosis and no longer functions like the book it was, leading me
to recall the terminology we use to describe how a book reacts when
something is done to it that shouldn't have been done to it, like
oversewing: eg, we call the book closing itself up after we have tried
to open it mousetrapping.  A book is not a mousetrap but certainly
better mousetraps need to be invented, and so better repairs of books
should be forthcoming, forthcoming in the sense of and similar to the
CIP (cataloging in process) program at LC, only I will call it RIP,
repairs in progress.  We should aspire to have all our work stamped with
the Good Bookbinding Seal of Upheaval.  Nonetheless, talc, steatite, and
soapstone:  it would seem that they are all synonyms of one degree or
another, or so my online dictionary and thesaurus states. See below.

steatite \'steE-e-,tuEt\ n
[L steatitis, a precious stone, fr. Gk, fr. steat-]
(1758)
1: a massive talc having a grayish green or brown color: SOAPSTONE
2: an electrically insulating porcelain composed largely of steatite P
steatitic \,steE-e-'tit-ik\ adj

soap7stone \'soEp-,stoEn\ n
(ca. 1681)
:a soft stone having a soapy feel and composed essentially of talc,
chlorite, and often some magnetite

talc \'talk\ n
[MF talc mica, fr. ML talk, fr. Ar t.alq]
(1610)
:a soft mineral Mg3Si4O10(OH)2 that is a basic magnesium silicate, is
usu. whitish, greenish, or grayish with a soapy feel, and occurs in
foliated, granular, or fibrous masses (hardness 1, sp. gr. 2.6-2.9) P
talcose \'tal-,koEs\ adj

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                  Conservation DistList Instance 5:50
                 Distributed: Thursday, April 16, 1992
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