Some dates are rare, but many can still be found in circulation. The wheat cent was mainstream and common during its time.However, cents minted from 1944 to 1946 were made from a special salvaged WWII brass composition to replace the steel cents, but still save material for the war effort, and are more common in circulation than their 1943 counterparts. These "steel pennies" are not likely to be found in circulation today, as they were later intentionally removed from circulation for recycling the metal and by collectors. Cents minted in 1943 were struck on planchets punched from zinc-coated steel which left the resulting edges uncoated. Both types were minted in 1982 with no distinguishing mark.
![history of us coins history of us coins](https://m.media-amazon.com/images/I/61cn3H14LxL._SL1050_.jpg)
![history of us coins history of us coins](https://i.ytimg.com/vi/7jjFmUMESN8/maxresdefault.jpg)
The San Francisco Mint produces regular and silver proof coinage, and produced circulating coinage until the 1970s. The Denver Mint also produces circulating coinage, mint sets and commemoratives.
![history of us coins history of us coins](https://images.vcoins.com/product_image/9/D/6/dBz48mSSnL2r5zMdjHt9aw7RkEo3b6.jpg)
The main mint is the Philadelphia Mint, which produces circulating coinage, mint sets and some commemorative coins. Today, four mints operate in the United States producing billions of coins each year.