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Variety · Silicate

Moss Agate

SiO₂

Chalcedony with green dendritic inclusions — not true banded agate.

Hardness7
Crystal systemTrigonal
ClassSilicate
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Moss Agate specimen

This is a polished slab of rock showing pyrolusite (MnO2) dendrites (the black “branching” or tree like deposit) in chalcedony (a microcrystalline variety of qu — Photo: Shannon Heinle · CC0

Moss Agate

Chalcedony threaded with green moss-like inclusions of hornblende or iron minerals — a beloved ornamental stone.

Intro adapted from Wikipedia (CC BY-SA).

Moss Agate is a mineral variety of Quartz, with the chemical formula SiO₂.

It crystallizes in the trigonal crystal system.

Key properties: Mohs hardness 7; typically white or green or red.

Collections: Gemstones, Collector Favorites.

Index entry. This entry combines official IMA/RRUFF species data with published physical-property data and a Wikipedia introduction — a full written entry hasn’t been published yet. Browse more M minerals or help write this entry.