Moss Agate Tumbled Stone

Moss agate is chalcedony - microcrystalline quartz, SiO₂, Mohs 7 - holding branched green inclusions of chlorite and hornblende. The "moss" is entirely mineral: green crystals that crept along fractures in silica-rich water and branched as they grew, before the chalcedony sealed around them.

Because the dendrites grew freely, no two stones carry the same scene. Some hold a single drifting branch, some a dense green field; the milky silica around them ranges from near-clear to cloud.

Honest naming: strict agate is banded, and moss agate is not - the name has carried by tradition, and we keep it as the trade and the centuries have. Dendritic chalcedony is the geologist’s term.

Asked often

Is there real moss inside?
No - nothing organic. The green branches are chlorite and hornblende, minerals that grew in branching forms before the stone sealed. Plant-like, but stone through and through.

Why does every stone look different?
The dendrites grew freely along fractures, so each stone holds its own scene. The variation is the stone, not a fault.

Is it dyed?
No. The green is the mineral itself; the milky ground is natural chalcedony.

How do I look after them?
Wipe with a soft, slightly damp cloth and dry. Hard-wearing at Mohs 7 and stable in daylight.

1. Carried in a pocket or a bag, or held in the hand.
2. Kept in a small dish, on a desk, or on a shelf - each stone is a little different.
3. Wipe with a soft, slightly damp cloth and dry; hard-wearing at Mohs 7.

Each stone is tumble-polished and unique, so a set varies a little stone to stone. Many keep a stone where they will see it each day, or carry one in a pocket; that is a matter of preference.

Pocket stones to keep and carry. Wipe with a soft cloth; hard-wearing at Mohs 7. Keep them together in a pouch so harder edges do not scratch softer stones.

• Stone: Moss Agate · dendritic chalcedony
• Hardness: Mohs 7
• Character: Milky ground · green branching scenes · each unique
• Treatment: None · undyed
• Form: Tumbled stones · polished, each unique · sold in a set
• Origin: India
• Care: Wipe with a soft cloth · keep dry

Pliny, in the first century, described agates marked with the figures of trees - dendrachates - and prized them for the scenes they carried. The fascination has never closed: stones that hold gardens have been set into rings, seals, and snuffboxes wherever lapidaries found them.

In European tradition moss agate was long held the gardener’s stone, carried for the fields and the planting - named here as what people believed. The scenes are the stone’s own; what grows in them is the keeper’s to read.