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gemstone main cabochon creation
min data

Mineral: quartz
Gem: moss agate (cryptocrystalline)
Size: 25 mm x 44 mm
Carat: 32.6 ct
Cut: freeform cabochon
Origin: unknown
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
It is a form of agate with embedded filaments and other patterns suggestive of moss. The "moss" has no relationship to organic matter, but simply resembles the look of moss. It can be green, but may also be brown, red, pink, or black. This agate has manly brown and red moss enclosed by the clear chalcedony.
Here are two closeup pictures of the moss. The moss is usually made up of iron or manganese oxide/hydroxide suspended in the agate.

The image on the left shows it swirlling freely in the agate, and the one below shows it following the contours of the chalcedony. The white banded area above the globular moss is sometimes referred to as a "fortification pattern".