mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions

Hardness: 6.5-7 on Mohs scale; Color: Cream, yellowish-white matrix with dark green to mossy green inclusions; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline/cryptocrystalline chalcedony); Cleavage: None; Conchoidal fracture.

Hardness: 6
Luster: Vitreous to waxy

Identified July 23, 2026More mineral →

Explore Moss Agate in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Forms primarily in hydrothermal and volcanic environments as silica-rich fluids fill cavities and fractures within volcanic rocks. The green dendritic or moss-like inclusions are typically minerals like chlorite, hornblende, or manganese oxides.

Uses & applications

Used extensively as an ornamental stone, in lapidary arts for cabochons, beads, carved figurines, tumbled pocket stones, and decorative jewelry.

Geological facts

Despite its name, Moss Agate is not actually a true agate because it lacks concentric banding; it is technically a chalcedony containing dark dendritic mineral inclusions that mimic moss or plant growth.

Field identification & locations

Identified by its smooth, polished waxy surface with distinctive dark green vegetation-like patterns embedded within a translucent to opaque creamy matrix. Commonly found in India, Brazil, Uruguay, and the USA.