mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide

Hardness: 6.5-7 (Mohs). Color: Clear or milky white with green, dendritic (moss-like) inclusions. Luster: Vitreous to waxy. Crystal Structure: Trigonal (microcrystalline/cryptocrystalline chalcedony). Cleavage: None. Specific Gravity: 2.58-2.64.

Hardness: 6
Luster: Vitreous to waxy

Identified May 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the infiltration of mineral-rich groundwater into cavities in volcanic or sedimentary rocks. The dendritic patterns are formed by the branching crystallization of iron or manganese oxides. Age varies by locality, often millions of years old.

Uses & applications

Used primarily in lapidary work for jewelry (cabochons, beads), decorative carvings, heart-shaped worry stones, and as a collector's specimen. It is also significant in modern healing crystal practices.

Geological facts

Despite its name, Moss Agate does not contain organic matter or real moss; the 'moss' is actually an inorganic mineral inclusion. It is often referred to as a 'stone of agriculture' or 'gardener's stone' in folklore.

Field identification & locations

Identify in the field by its translucent body combined with dark green, branch-like patterns. Common locations include India, Brazil, Uruguay, and the United States (notably Montana and Oregon). Collectors look for high translucency and dense, intricate 'moss' patterns.

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