Idocrase is a rare gemstone which belongs to the silicate group of minerals. It exists mostly in shades of green but can also be yellow-brown and pale blue. This gem stone is named as Vesuvianite since the first samples were found on the Mt. Vesuvius volcano.

This mineral was first identified and named by the famous German gemologist Abraham Gottlob Werner in 1795. The name idocrase is from Greek and means ‘mixed form’, since its crystals show a mixture of other mineral forms.

Idocrase is rare and transparent idocrase crystals which have a vitreous luster are even rarer. Opaque idocrase is similar to jade with a resinous luster. Idocrase is slightly softer than quartz, with a rating of 6.5 on the Moh’s scale of hardness.