sedimentary

Tree Agate

Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony

Hardness: 6.5–7 (Mohs scale); Color: White or pale green background with dark green dendritic inclusions; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific gravity: 2.58–2.64.

Hardness: 6
Luster: Vitreous to waxy

Identified March 30, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the infiltration of manganese or iron oxides into fissures of chalcedony. This process typically occurs in volcanic or sedimentary environments where silica-rich groundwater deposits minerals over millions of years.

Uses & applications

Primarily used in jewelry (cabochons, beads, pendants), ornamental carvings, and as a popular specimen for rock collectors and metaphysical enthusiasts.

Geological facts

Despite the name, the green 'branches' are not fossilized plant matter; they are dendritic mineral inclusions. It is often referred to as the 'Stone of Plentitude' in folklore and has been used since ancient times for talismans.

Field identification & locations

Identify in the field by its characteristic mossy or tree-like patterns and its smooth, waxy texture when tumbled. Common locations include Brazil, India, Uruguay, and the USA (Montana/Washington). Look for translucent to opaque white quartz with distinct green branching structures.

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