In 1945, Count Taaffe, a Dublin gemologist found a pale mauve stone in a jewelers junk box that resembled spinel in appearance and properties but showed distinct double refraction. The stone was sent to the British museum for testing where they determined it to be an unknown mineral. Although its refractive index is nearly the same as spinel, it can be differentiated by its double refraction and uniaxial negative character.
Despite diligent search, it was not until 1949 that another stone was found in a parcel of stones from Sri Lanka. A third stone was found in 1957 by Robert Crowningshield of GIA and a fourth stone some 10 years later. Since then, more gemologists have been aware of taafeite and stones continue to be discovered. We discovered some taafeites in our mine run material from Tunduru, Tanzania and have started re-checking all our stones especially the spinels for any evidence of double refraction which with the correct refractive index would confirm their identity as taafeite.
