LA-ICP-MS Analysis of Natural Blue Sapphires Enhanced with the New E(IM1)-Method with Details of Trace Element Concentrations

Fig. 56 Expanded area of Fig. 55 shows details of the color zoning, and the points measured by LA-ICP-MS. The numbers refer to the measured points. color zoning is subdivided into orangy-pink “Padparadscha” (P), pastel blue sapphires (S), cornflower blue sapphires (CBS) and royal blue sapphire (RBS). Beryllium concentrations are restricted to the zones outside of this color banding produced by the new enhancement method (1-5 and 23-24)

Fig. 57 The chemical compositions (in ppm) in a profile across the blue sapphire enhanced with the new method as determined by LA-ICP-MS. Note: Chemical compositions are dominated by trace elements Cr, Fe, and Ti - light elements, such as Be and Mg, are subordinate. The Beryllium concentrations are restricted to the outer zone and do not exceed 30ppm. Magnesium (Mg) is found in the entire profile with concentrations of about 50 to 100ppm. Note: Zones rich in Mg at the absence of Be are found at points 6 to 10. At Ti below 150ppm, Cr above 200ppm and Fe above 1000ppm "Padparadscha" colors may be formed. This corresponds well to the observed color banding in the gemstone. Note: Point No. 10 (See arrow) is a “Padparadscha” color band containing Fe, Cr, V, Ti and Mg but no Beryllium.

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