Geographic origin determination of gem corundum. Its accuracy and limitation

Abstract

Geographic origin determination of a gem-corundum has to restrict the geographical area from where each crystal has occurred, so that it needs background of a gemstone to determine geological environment and global tectonics from which the gemstone has been derived. In addition to standard gemmological test, UV-Visible and infrared spectrophotometry, Raman microspectrometry, EDXRF and LA- ICP-MS analysis are operated to identify them.
It is noted that the result of locality identification must be regarded as an opinion of a laboratory that testes a particular gemstone, and it is not what to be proved.