Re: Vermicullite
Charles Powell (cpowell@mojave.wr.usgs.gov)
Wed, 21 Feb 96 06:34:09 PST
Vermicullite is a product of Mica, generally Biotite, in which the water
has been driven off by heating. Mica's are silicate minerals (not clay
minerals) which form in sheet structures: one sheet of silicate + other
elements separated by a sheet of water (not exactly but for purpose of this
explanation, correct), followed by another sheet of silicate. As far as
being biodegradeable it is moreso than the silica sand we use, but less so
than the peat. But since its a, more or less, natural product it shouldn't
be a problem in any case.
Chuck
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Charles Powell, II
U. S. Geological Survey, MS 915
345 Middlefield Rd.
Menlo Park, CA 94025
Tel.: 415-329-4985
E-mail: cpowell@mojave.wr.usgs.gov
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