Trace elements of sapphires reportedly from Nigeria

Abstract

Trace elements of blue, green and yellow sapphires reportedly from Jos and Adamawa plateaus were quantitatively analyzed with LA-ICP-MS to compare with each origin and Mambilla, the other sapphire mining locality in Nigeria. Sapphires from these localities are all related to Tertiary alkali basalts intruded through Precambrian migmatite-gneiss complex. Jurassic granites occur only in the basement complex in Jos plateau. Since corundum crystals in alkali basalt are xenocrysts, trace elements may indicate differences of original hosts of xenocrysts. Nigerian sapphires can be ideal samples to discuss chemical variation of xenocryst host for the purpose of origin determination of basalt-related sapphires.