xanthophyllite

xanthophyllite

[‚zan·thə′fi‚līt]
(mineralogy)
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References in periodicals archive ?
The most common brittle micas are dioctahedral margarite, [([Al.sub.2]).sup.VI][([Si.sub.2][Al.sub.2]).sup.IV][O.sub.10][(OH).sub.2]Ca, dominantly trioctahedral clintonite and xanthophyllite, [[(Mg > Fe,Al).sub.2-3].sup.VI] [([Si.sub.1.3][Al.sub.2.7]).sub.IV][O.sub.10] [(OH).sub.2]Ca, and chloritoid, [[(Al,[Fe.sup.2+]).sub.2-3].sup.VI] [([Si.sub.2][Al.sub.2]).sup.IV][O.sub.10][(OH).sub.2](Mg,[Fe.sup.2+]).
Ambiguities in nomenclature have historically arisen in the classification of the trioctahedral brittle micas: seybertite, valuevite, brandisite, holmite, xanthophyllite and others have all been used in the past to denote separate mica species.
At that time the accepted mineral name was "xanthophyllite, variety waluewite." Both of those names were subsequently discredited in favor of clintonite (named after New York Governor DeWitt Clinton in 1828).