BLUE SAPPHIRES FROM MOGOK, MYANMAR: A GEMOLOGICAL REVIEW

Burmese sapphires are among the most coveted colored gemstones in the world. The historical importance of this source and the fine quality of its high-grade material contribute to the legendary status of these gems. Since Mogok is such a long-known source, there are many classic studies available, but modern analytical data are often missing or not up to current standards. This article summarizes the characteristics of Burmese sapphires, including standard gemological properties, inclusion observations, and spectroscopic and trace element analyses. This information was collected from hundreds of blue sapphires that GIA's field gemologists sampled while visiting different mining regions in Mogok over the past decade. Our observations indicate that these sapphires show a wide range of blue color intensities but very consistent inclusion scenes. Trace element chemistry did not show any significant differences between various regions apart from a wider range of Fe concentrations in sapphires from north of Mogok. Rare observations such as orange fluorescence and unusual FTIR spectra can be attributed to the chemical compositions of the sapphires.

Automated summary

Burmese sapphires are highly sought after for their historical significance and fine quality, showing a wide range of blue color intensities and consistent inclusion scenes. Differences in iron concentrations can be observed, with rare occurrences such as orange fluorescence and abnormal FTIR spectra attributed to the chemical compositions of the sapphires.