In 1794 the the United States began to produce the half dollar. That first year only 5300 were minted so you can understand why these would be rare coins. There were 150,000 minted in 1804 but they ended up using the 1803 dies, so no 1804 pieces exist. In 1836 the Philadelphia mint produced the dies for the half dollar that would be used at the new New Orleans mint. Ten test samples were minted at the Philadelphia mint, and they were place into the mint safe along with rare 1804 dollar.