Moss Agate

Physical Properties

Hardness: 6.5–7 (Mohs); Color: Green, earthy white, grey; Luster: Waxy to vitreous; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None; Specific Gravity: 2.58–2.64

Formation & Geological History

Formed through the deposition of silica in fissures or cavities in volcanic rocks. The distinctive patterns are created by inclusions of manganese or iron oxides that form dendritic (moss-like) patterns as the silica cools.

Uses & Applications

Primarily used for jewelry (cabochons), ornamental carvings, decorative stones, and by collectors. In historical times, it was believed to be a stone for gardeners and agriculture.

Geological Facts

Despite its name, Moss Agate does not contain organic matter or real moss; the 'moss' is actually mineral inclusions. It is known as the 'Stone of Abundance' in many folklore traditions.

Field Identification & Locations

Identify in the field by its characteristic green dendritic or filaments patterns trapped inside a translucent to semi-opaque chalcedony body. Common locations include India, Brazil, Uruguay, and parts of the United States like Montana.

Identified on: 4/13/2026

Mode: Standard