Investment criteria

Only natural, untreated gemstones of the highest quality and with famous origins qualify for investment purposes: especially rubies, sapphires and emeralds, but also spinels, tsavolites and alexandrites.

Investment stones should be of a minimum size and must have an internationally recognized certificate from laboratories like GIA, SSEF Gübelin or GRS, which confirms the stone’s origin and that it is of a natural colour (i.e., untreated – NTE, No Thermal Enhancement).