mineral

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Hardness: 6.5-7 (Mohs scale), Color: White or clear base with green branching inclusions, Luster: Vitreous to waxy, Crystal Structure: Trigonal (microcrystalline), Cleavage: None, Specific Gravity: 2.58–2.64

Hardness: 6

Identified April 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed in volcanic rock cavities or hydrothermal veins through the deposition of silica. The green 'tree-like' patterns are caused by manganese or iron oxides/silicates (like chlorite) forming moss-like or branch-like inclusions during crystallization.

Uses & applications

Primarily used for ornamental purposes, jewelry (pendants, cabochons), tumbled stones for collecting, and metaphysical/holistic practices.

Geological facts

Despite its name, Tree Agate is not a true Agate because it lacks the classic concentric banding. It is technically a variety of Chalcedony containing dendritic inclusions.

Field identification & locations

Look for a translucent to opaque white base with distinct green mossy or fern-like patterns. Common in India, Brazil, and the USA. It is durable and takes a high polish, making it a favorite for beginner lapidary enthusiasts.