moss agate

American  

noun

1. a kind of agate or chalcedony containing brown or black mosslike dendritic markings from various impurities.

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moss agate British  

noun

1. a variety of chalcedony with dark greenish mossy markings, used as a gemstone

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Etymology

Origin of moss agate

First recorded in 1790–1800

Example Sentences

Joel Otterson’s intimate sculptures set moss agate in silver and brass at Ehrlich Steinberg.

From The Wall Street Journal • Feb. 27, 2026

Citrine, aventurine and moss agate are said to attract abundance.

From Los Angeles Times • Mar. 31, 2018

The Indian student exhibited the odd gold emblem with the pine tree tracing on the moss agate.

From Jack Ranger's Western Trip Or, from Boarding School to Ranch and Range by Young, Clarence

Included matter of a green colour, like fragments of ``green earth,'' embedded in the chalcedony and disposed in filaments and other forms suggestive of vegetable growth, gives rise to moss agate.

From The Project Gutenberg Encyclopedia Volume 1 of 28 by Project Gutenberg

The shell contained a piece of clear quartz crystal, and the bowl a moss agate.

From The North American Indian by Curtis, Edward S.