mineral

Moss Agate

Chalcedony (Silicon Dioxide / SiO2)

Hardness: 6.5–7; Color: White or clear base with green, red, or black tree-like inclusions; Luster: Waxy to vitreous; Crystal Structure: Cryptocrystalline; Cleavage: None; Specific Gravity: 2.58–2.64

Hardness: 6
Luster: Waxy to vitreous

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the deposition of silica-rich groundwater in volcanic rock cavities. The 'moss' patterns are caused by manganese or iron oxide inclusions during formation, often over thousands of years.

Uses & applications

Predominantly used in jewelry (cabochons), ornamental carvings, and as a popular specimen for rock collectors and practitioners of metaphysical healing.

Geological facts

Despite its name, it does not contain organic matter or moss; the patterns are purely mineral. It was historically viewed as a stone of agriculture that helped gardeners grow healthy crops.

Field identification & locations

Identify by its translucent body with moss-like dendritic patterns. Commonly found in India, Brazil, Uruguay, and the United States (specifically Central Europe and the Northwest). Collect by looking for translucent nodules in gravel beds or volcanic regions.