Maw-sit-sit is one of the more unusual gemstones in the world, from its curious name to its variable chemical composition. It is a recent find, first identified in 1963 by the late Swiss gemologist Dr. Edward Gubelin. It was named after the village in northwestern Burma which is close to the site where it was first found.
Maw-sit-sit is considered to be a rock rather than a mineral, since it is composed of a number of different minerals, including kosmochlor (a mineral related to jadeite) and varying amounts of jadeite and albite feldspar. It is often classified as a member of the jade family but it is not truly a variety of jadeite.
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