1927 is not a rare date for Lincoln cents. Look on the front of the coin to see if there's a small mint mark letter below the date. It may be blank or there may be a D or S.
Numismedia lists the following approximate retail values as of 04/2010:
No mint mark (Philadelphia):
Very worn condition - $0.10
Moderately worn - $0.23
Slightly worn - $0.81
Almost no wear - $4.60
Uncirculated - $9.00 to $107.90 depending on quality
"D" mint mark (Denver):
Very worn condition - $0.21
Moderately worn - $0.58
Slightly worn - $1.44
Almost no wear - $24.50
Uncirculated - $55.20 to $624.00
"S" mint mark (San Francisco):
Very worn condition - $0.46
Moderately worn - $1.15
Slightly worn - $1.90
Almost no wear - $28.40
Uncirculated - $62.40 to $630.00
The last U.S. half cent was made in 1857.
1 US cent has the same value the world over! i.e. 1 US cent
That is Scott number US 1721. It has a 75 value new and 15 cents used.
1856 3 cent coin value
About 1 cent.
It's still worth one cent US.
A 1997 US one cent piece? is a Lincoln cent and only face value.
It's worth exactly one cent.
A 1942 US Wheat cent is common, average value is 3 cents.
The US has minted 1¢ coins since 1793, and at 3 different mints so there are many hundreds of different possibilities. Please post a new, separate question with the coin's date. Alternately, look for questions phrased "What is the value of a <date> US cent?", e.g. "What is the value of a 1927 US cent?" Nearly every date has been asked about and answered.
The coin has face value only.
The only US coin ever struck in steel was the famous 1943 Lincoln cent, minted when copper was diverted to making ammunition. All buffalo nickels are made of an alloy of 75% copper and 25% nickel. Please see the question "What is the value of a 1927 US nickel?" for more information.