Is a Barium Sulfate with formula BaSO4 and hardness of 3-3.5.Common material in massive form and it may looks like marble, while in gem quality is not easy to find; although there are crystals big enough to be facet, is quite difficult to cut and polish especially on the corner junctions. Due to his low hardness it’s a collector stone. We can find it in various colours and in this case the yellow is typical for the Sardinian,an Italian old deposit .
This stone has been cut in Italy by Luigi Mariani and is a superb gem ,a museum piece!Of this carat weight is of the best in the world.
Weight: 51.06 ct.