Note 38 — Chapter XII
Reading edition
Later mints were established at Denver, San Francisco, and New Orleans. Assay offices for refining and determining the purity of bullion have been established at New York, St. Louis, Deadwood, Helena, Boise, Carson City, Salt Lake, Seattle, and Charlotte, North Carolina. To give strength and hardness to gold and silver coins an alloy of copper equal to one tenth of their weight is added.