• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.17-26
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• 2008

The Madagascar garnets wear mainly found as a porphyroblast in gneiss and classified into rhodolite, purple almandine, and brown almandine based on compositional characteristics and color. UV-visible analysis strong absorption bands, 400, 428, 504, 521, and 572 nm, were observed for rhodolite and purple almandine, and main absorption bands of 433 and 502 nm observed for brown almandine. For FT-IR analysis a strong absorption band of $640\;cm^{-1}$ was observed for rhodolite, two strong bands of 628 and $651\;cm^{-1}$ observed for brown almandine, and two weak absorption bands of 635 and $653\;cm^{-1}$ observed for purple almandine. Single distinct absorption band, $3552\;cm^{-1}$, was observed only for rhodolite. It is possible to distinguish rhodolite from purple or brown almandine by considering overall characteristics of the rhodolite such as color, RI, UV-visible absorption, FTIR absorption etc.

• Journal of the Korean Chemical Society
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• v.17 no.5
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• pp.353-356
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• 1973

A unique method of destructive analysis has been developed for the study of gaseous impurities in minerals. Samples are crushed in a high vacuum sample system of a research mass spectrometer. This is done by means of a suitably designed crusher which is incorporated in the inlet system of the instrument. Crusher elements are constructed of tungsten carbide. The mass spectrometer used for this preliminary study has a detection sensitivity of about $10^{-10}cc$at STP. In a study of rhodolite garnets obtained from near Lavonia, Georgia, U.S.A., the gases$H_2$, $O_2$, $H_{2}O$, $CO_2$, CO, and $CH_4$have been identified and their composition determined.