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

She sent me fifty yards down the hill to pick up a piece of broken bottle which she insisted was moss agate!

From From Sea to Sea Letters of Travel by Kipling, Rudyard

Its colors are delicately arranged in stripes or bands, or blended in clouds. µ The fortification agate, or Scotch pebble, the moss agate, the clouded agate, etc., are familiar varieties.

From Webster's Unabridged Dictionary by Webster, Noah