Smithsonian National Museum of Natural History

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Department of Mineral Sciences

Izalco Volcano
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Quantitative Analysis

Approximately 1000 analysis for major and trace elements are performed per year in the XRF laboratory. The analyzed rocks vary from basalts, rhyolites, to granites and metamorphic rocks. Trace elements are also analyzed in minerals from pegmatites.

XRF
A. Cs vs. Ta in muscovites from pegmatites in Maine.

XRF
B. K/Rb versus Sr in feldspars from pegmatites in southern California.
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Qualitative Analysis

Occasionally specimens from other Museums are analyzed for identification by mean of qualitative analysis. Specimens may include rocks, coins or possible meteorites.

XRF
 

XRF qualitative analysis of a 5$ coins from the M&P Co. (1849). The purpose was to establish the chemical differences between the original and a restrike. The original displayed a Cu KA line with slightly higher intensity. The restrike displayed a Ag LA with higher intensity than the original.