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gemstone main cabochon creation
min data

Mineral: quartz
Gem: black skin agate (cryptocrystalline)
Size: 26x36 mm & 21x34 mm & 29x39 mm
Carat: 49.2 ct & 36 ct & 71+ ct
Cut: freeform cabochon
Origin: India
General Info: Agate (achates) was named from the river Achates, now the Drillo, in Sicily, where the stone was first identified. It is cryptocrystalline quartz (micro crystals) usually with a banded pattern (although not always).
Additional Information
Black skin agate from India comes in a variety of types. My favorite are those containing moss. There are fortifications, straight line patterns, and tubes in some pieces. The agate is really hard and takes a great polish, but some of the moss can be troublesome and will undercut or pit. (Some does not.)

Cabs cut by author.

Closeups of blackskin agate Closeups of blackskin agate