It is 100% copper.
The first Indian head cent was issued in 1856. A U.S. cent dated 1821 is a LIBERTY HEAD large cent. Most show heavy wear and are valued at $15.00-$40.00 for average circulated coins.
It was still commonly called a penny but was also referred by its formal name as a cent. Today, collectors call the cents made prior to the flying eagle cent in 1856 as "large cents" as they were about the size of a half dollar as opposed to the small cents that circulate today.
All US Large cents (1793-1857) are struck on copper planchets
Large cent is equivalent to rectangle
You don't have a large cent because the last large cent was made in 1857. Any US cent dated 1863 should be an Indian Head cent. What you might have is a privately made token or something of that sort because it is not a US mint product if it is a large cent or not an Indian Head Cent.
There were three different types of Large Cents minted that year: a Flowing Hair Large Cent, Chain Reverse; a Flowing Hair Large Cent, Wreath Reverse; and, a Liberty Cap Large Cent. What coin do have?
The United States first minted the large cent in 1793.
1814 is the last year of issue for the "Classic Head" large cent. To see what it looks like on your browser type in Classic Head large cent, click images & search.
This is a Coronet Large Cent. In decent condition $40 to $50...In excellent condition $1000 to $1500
The US Large Cent was first struck in 1793 under the authority of the United States Govenrment. These coins were minted every year from 1793 through 1857 with the exception of 1815 when a copper shortage prevented production. The large size of these cents was a result of laws which required the cent to be twice the weight of a half cent. By 1857 the cost of producing large copper coins had risen. The result was the half cent was discontinued and the Large cent was replaced with the smaller cents that are familiar today.
Numismedia lists the following approximate retail values as of 02/2010: Very worn condition - $54 Moderately worn - $270 Slightly worn - $660 Almost no wear - $2,830 Uncirculated - $7,500 to $12,060 depending on quality
Please look at the coin again, 1857 was the last year the US made a large cent.