The first coins made by the US Mint was in 1793.
No U.S. coins were ever made from lead.
copper
US coins were first struck by the US mint located at Philadelphia, Pennsylvania in 1793.
After coins are made they are bagged and distributed to banks in the US through the Federal reserve system.
Your question needs to be rephrased. "Denver coins" are simply ordinary US coins (cents, nickels, dollars, etc.) that were struck at the US Mint facility in Denver.
US paper money is made at the Bureau of Engraving and Printing, coins are made at the US mint.
San Fransisco
No US dollar coins were made in 1950
Circulating US coins are made in Philadelphia and Denver. Proof coins are made in San Francisco and bullion coins are struck at West Point. Other mints, now closed, were located in New Orleans, Carson City, Charlotte, and Dahlonega GA.
Many different metals.
Please, rephrase question.