Research

A Purple Sapphire Containing Interesting Inclusions: Formation Insights

Recently, the authors examined a cushion-shaped purple sapphire weighing 3.56 ct (Figure 40a). The RIs were 1.762–1.770, yielding a birefringence of 0.008, consistent with sapphire. FTIR spectroscopy confirmed its identification as corundum. The stone displayed strong red fluorescence to long-wave (365 nm) UV radiation (Figure 40b). Chemical analysis by EDXRF spectroscopy revealed appreciable Cr (about 720 ppm) and Fe (approximately 1,200 ppm), along with some Ti (around 230 ppm).