sedimentary

Tree Agate

Silicon Dioxide (SiO2) with Chlorite/Manganese inclusions

Hardness: 6.5-7 (Mohs scale), Color: White with forest-green dendritic inclusions, Luster: Vitreous to waxy, Crystal Structure: Trigonal/Microcrystalline, Cleavage: None (conchoidal fracture), Specific Gravity: 2.6

Hardness: 6

Identified March 25, 2026More sedimentary →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in volcanic cavities or hydrothermal veins as groundwater rich in silica deposits layers of microcrystalline quartz. The 'tree-like' patterns are created by trace minerals like manganese or iron oxide seeping into the cracks during formation.

Uses & applications

Primarily used for lapidary work, jewelry (beads, cabochons, carvings), decorative ornaments, and widely used in the metaphysical and gemstone collecting community.

Geological facts

Despite the name, Tree Agate is technically a 'dendritic chalcedony' rather than a true agate, as it lack the concentric banding typical of agate specimens. It has ancient associations with agriculture and was often buried in fields to promote bountiful harvests.

Field identification & locations

Identify by its opaque white base and mossy, branch-like green patterns. In the field, look for nodules with a waxy exterior. Common locations include India, Brazil, Uruguay, and the United States. It is popular for beginners because of its high durability.

Other sedimentary specimens

See all

Sandstone or Siltstone

Arenite (if sandstone)

Sedimentary

Sandstone

Arenite (primarily SiO2)

sedimentary

Shale or Slaty Mudstone

Argillaceous sedimentary rock

sedimentary

Chert Breccia

Brecciated Chert (Microcrystalline Silica)

sedimentary

Sandstone (Quartz-rich)

Arenite (SiO2)

sedimentary

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

sedimentary