Dendritic Agate

Physical Properties

Hardness: 6.5-7 (Mohs scale); Color: Translucent white to gray base with black/brown tree-like patterns; Luster: Waxy to vitreous; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None; SG: 2.58-2.64

Formation & Geological History

Formed when mineral-rich groundwater (containing manganese or iron) seeps into fractures and cavities of rhyolite or chert, precipitating out in branching patterns known as dendrites.

Uses & Applications

Primary use is in jewelry (cabochons), lapidary arts, and as a collector's specimen. It is highly valued in metaphysical communities as the 'Stone of Plenitude.'

Geological Facts

Despite its name, it is technically a chalcedony rather than a true banded agate. The 'plant-like' patterns are purely inorganic mineral growths and not actual fossils.

Field Identification & Locations

Identify in the field by its translucency and characteristic branch-like 'fern' inclusions. Commonly found in Brazil, India, Madagascar, and the USA (notably Montana and Oregon).

Identified on: 4/26/2026

Mode: Standard