While all US nickels contain copper, none contain enough of the metal to appear coppery in color. Your coin was probably tarnished by exposure to heat, chemicals, or some other environmental contaminant; in that case it would only be worth 5 cents.
All US nickels (except for silver war nickels) are 75% copper and 25% nickel, with a present melt value of 4.9 cents.
If you found it in change your nickel is only worth face value. US nickels made from 1866 to mid-1942 and from 1946 to the present are made of a copper-nickel alloy, not silver. In fact, no circulating US coins have contained any silver since 1969.
5 cents. It's not silver. All US nickels except the famous "war nickels" from 1942-45 are made of the same metal, an alloy of 75% copper and 25% nickel.
At the time of writing just a bit shy of 7 cents. Keep in mind though that minting or exporting US nickels is currently illegal and there are no buyers for nickels for bullion purposes (because you can get as many boxes as you want from the bank, for 5 cents each, no one is going to pay 6 or 7 cents for a nickel).As of May 24 2011 the melt value of a nickel in circulation is $.0616147. This price is set with copper at a spot price of $4.0032 per lb and nickel at $10.3491 per lb. The value will change as the price of copper and nickel change.
All 1994 US nickels were struck in the same alloy of 25% nickel and 75% copper. Any 1994 nickel that's copper in color was almost certainly damaged by exposure to heat or chemicals, or was plated with that metal. You can also check the coin's weight; it should be 5 grams. If it's very much different from that amount you should have it inspected in person by a dealer or knowledgeable collector.
If you have a US nickel, it is either coated with copper or has changed color due to exposure to some chemical and has no special value. If it is a 1942 Canadian nickel, it varies from $.40 to $1.75 in circulated conditions, $3 and up in uncirculated grades. The material is called "tombac" and is an alloy of copper and zinc.
The first 5-cent US nickel was made in 1866, the 3-cent nickel in 1865, and the copper-nickel flying eagle 1-cent in 1856.
All US nickels (except for silver war nickels) are 75% copper and 25% nickel, with a present melt value of 4.9 cents.
25 cents. All 1974 quarters were made from copper-nickel.
No such (US) coin exists because the copper-nickel 3 cent piece was not minted until 1865.
All 2010 US nickels were struck in the standard cupronickel alloy. A nickel that appears to be made of copper could have been discolored by heat or chemical exposure, or it might be copper-plated. The latter is a very common high-school chemistry experiment.
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.
Please check your coin again and post a new, separate question. The first US nickels were struck in 1866 and they were never made of pure copper.
All US state quarters intended for circulation are made out of copper-nickel, 92% copper, 8% nickel.
US quarters didn't contain any nickel until 1965. 1964 and earlier quarters were made of an alloy of 90% silver and 10% copper. Please see "What is the value of a 1941 US quarter?" for more information.
If it is a US nickel, it is 25% nickel, 75% copper. If it is a Canadian nickel I believe it is 100% nickel.
If you found it in change your nickel is only worth face value. US nickels made from 1866 to mid-1942 and from 1946 to the present are made of a copper-nickel alloy, not silver. In fact, no circulating US coins have contained any silver since 1969.