ASSAY. A chemical examination of metals, by which the quantity of valuable or precious metal contained in any mineral or metallic mixture is ascertained. 2. By the acts of Congress of March 3, 1823, 3 Story's L. U. S. 1924; of June 25, 1834, 4 Shars. cont. Story's L. U. S. 2373; and of June 28, 1834, Id. 2377, it is made the duty of the secretary of the treasury to cause assays to be made at the mint of the United States, of certain coins made current by the said acts, and to make report of the result thereof to congress.