Other Blog. Pink Sapphire Pink Sapphire is the colored stone in Corundum family, with maximum hardness inferior to diamond, resulting in resistance to scratch. Ruby Ruby is the gemstone in the Corundum family with hardness inferior to diamond. It is popular for use in making jewelry with high commercial value. Emerald Emerald is crystal mineral in Beryl family, consisting of Chromium (Cr) and resulting in white. Premium emerald must be transparent with even color over the grain.
