English Jadeite Cited by user Kent G. Budge on 25 Dec 2021 Jadeite is a pyroxene mineral with composition NaAlSi2O6. It is hard (Mohs hardness of about 6.5 to 7.0), very tough, and dense, with a specific gravity of about 3.4.
English Langgan Cited by user Carlotm on 26 Jun 2021 Langgan 琅玕 is the ancient Chinese name of a gemstone which remains an enigma in the history of mineralogy; it has been identified, variously, as blue-green malachite…