sedimentary

Tree Agate

Dendritic Chalcedony (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Green and white; Luster: Vitreous to waxy; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Green and white
Luster: Vitreous to waxy

Identified May 17, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Green and white; Luster: Vitreous to waxy; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed via the accumulation of silica-rich water in volcanic rock cavities or sedimentary fissures, where manganese or iron oxides create dendritic patterns. Over millions of years, these minerals solidify into agate.

Uses & applications

Primarily used in jewelry (cabochons, beads), decorative carvings, and as a popular specimen for collectors and holistic practices.

Geological facts

Despite its name, the fern-like patterns (dendrites) are not fossilized plants but are mineral inclusions of iron or manganese that grew in branching patterns during formation.

Field identification & locations

Identify by its characteristic green spots or branching moss-like patterns against a white translucent or opaque background. Found frequently in India, Brazil, and the USA.