What is a block of artificial stone in the form of a brick, used for paving; also, a molded sample of solidified cement or mortar for use as a test piece for showing the strength of the material called?

briquette — A block of artificial stone in the form of a brick, used for paving; also, a molded sample of solidified cement or mortar for use as a test piece for showing the strength of the material. (Webster's 1913.)

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