United States Mint, Denver

From http://www.usmint.gov/about_the_mint/mint_facilities/index.cfm?action=DV_facilities:

n 1858, when gold was discovered in Colorado, hundreds of merchants, miners and settlers moved in for their stake. A year later, the city of Denver was founded; and in 1863, the U.S. government established a mint facility there. Today, the United States Mint at Denver manufactures all denominations of circulating coins, coin dies, the Denver "D" portion of the annual uncirculated coin sets and commemorative coins authorized by the U. S. Congress. It also stores gold and silver bullion.

For its first 46 years, the United States Mint at Denver was only an assay office in the Clark, Gruber and Company Bank Building. Miners brought in gold dust and nuggets to be melted, assayed and cast into bars stamped with their weight and quality. By 1895, the Assay Office was booming, bringing in more than $5.6 million in gold and silver deposits annually.

In 1904, the government decided to convert the Assay Office into a working mint, and built a much grander facility, an Italian Renaissance style building modeled after a Florentine palace. In 1906, its first year in operation, the new Mint produced 167,371,035 gold and silver coins valued at $27 million. Today, the Denver Mint's output can exceed 50 million coins a day.