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

They made the half-mile at a quick trot, and as they ran the rocks and the sky and the air between the cliffs turned a turbid green, like the color in a moss agate.

From The Song of the Lark by Cather, Willa Sibert

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

Before Jack was aware what the man was up to he had grabbed from his finger the curious moss agate emblem.

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