This attractive chalcedony is from the Mamuju area, Weat Sulawesi Province, Indonesia. This material which is a fairly recent find (2016) is from a series of deposits from a beach at Pantai Ngalo. The trade name for this material is “Grape Agate”. The deposits contain a handful of other minerals but the chalcedony is the variety much sort after. The chalcedony is also said to actually be a botryoidal form of amethyst. It can be found in colors varying from neutral hues to greens and purples. This piece has the attractive purple as well as greenish colored clusters or grape-like crystalline formations. This piece measures 5 x 2 1/4 x 1 7/16 inches or 127 x 57 x 37 mm.