Minerals From MacedoniaIII. Determination of Calcite and Aragonite in Mineral Mixtures Using FT IR Spectroscopy

The appearance of the VI mode (1083 em-I) in the Ff IR spectrum of aragonite (absent in the spectrum of calcite) as well as the lower frequency of the V4 mode in the spectrum of aragonite (713 and 700 em-I) than in that of calcite (732 em-I) made it possible to detect the presence of aragonite in calcite and to determine its content. Similarly, the higher frequency of the V4 mode in the spectrum of calcite (732 em-I) than in aragonite (713 and 700 em-I) was used to detect impurities as well as to determine the content of calcite in aragonite.