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USGS · 70014849

Near infrared detection of ammonium minerals

M. D. Krohn·S. P. Altaner
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Abstract

Diagnostic near-infrared spectral features have been identified for minerals with ammonium (NH (super +) 4 ) bound in the crystal structure. Spectral bands near 2.12, 2.02, and 1.56 mu m are characteristic of synthetic and natural NH 4 -bearing minerals. Laboratory spectra of NH 4 -bearing minerals are distinct from spectra of OH-bearing minerals and have diagnostic shifts in band position among different mineral types. NH 4 -bearing minerals were detected at several mineralized hot-spring deposits in the western U.S. by means of hand-held and airborne instruments. Near-infrared detection of NH 4 -bearing minerals may provide useful information for prospecting for certain ore deposits and may provide a better understanding of the nitrogen cycle within geologic environments.

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M. D. Krohn, S. P. Altaner. 1987. Near infrared detection of ammonium minerals. https://doi.org/10.1190/1.1442362

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