A "Doubled Die" error on a coin is the result of a fault in the die manufacturing process creating either a fully complete image at an angle to the original or, most commonly, what might appear as a blurred image on the coin such as you may get if you move a camera at the point of taking the photo. Such dies should never reach the point of striking a coin.
The term "Doubled Die" should not be confused with the terms "Die Clash", which is the obverse and reverse dies meeting without a blank between them giving a slight mirror image on both sides of the coin, or a "Double Strike" which is the same blank being struck twice by the same dies.
There was an error in the 2000-P Sacagawea Dollars. It was boldly doubled tail feathers. Only about 5,500 of the 767,140,000 are believed to be errors.
Not all 1943 nickels are double die errors with doubled eyes. The doubled eye variety is a well-known error for 1943 Jefferson nickels, but it is not present on all coins from that year. If you have a 1943 nickel, it would be best to have it authenticated by a professional coin grader to determine if it is the double die variety.
Simple answer is: 1909-S / 1909-S V.D.B. / 1914-D / 1922 no D / 1931-S and the 1943 Bronze and 1955 Doubled-Die error coins.
A "Die Error" would be an error caused by a defective, damaged, misaligned or incorrectly engraved die. It could also be a mismatched die pair, like the Golden Dollar reverse with a Washington Quarter obverse, but that would be better know as a Mule error. Dies that crack or break leave raised areas onthe coins where the metal on the die was missing. If the dies hit each other with no planchet (Blank Coin) between them, it can leave a slight image of the opposite die on the resulting coins. This is called Die Clash. If the coin is off center on one side and normal on the other it's call a MAD error or MisAligned Dies. One of the more valuable and rarest die error is the Doubled Die error. This happens with the dies are engraved with a second image, word or date slightly off of the intended image. This would be like the famous 1955 or 1969-S Doubled Die Obverse. Just my 2ยข worth.
Penny
There are no known 1953 "Doubled Die" errors at this time, but machine doubled errors exist for all U.S. coins. Take it to a coin dealer for an assessment.
If it is certified by one of the recognized authorities on error coins, it could be worth up to $385. That's what the latest copy of the Numismatic News Coin Market lists for the 1972 doubled die variety in Uncirculated condition. Even the slightest amount of wear will reduce that value dramatically. But it is possible that you have a much more common (and basically worthless) example of "die bounce". The doubled die error occurs only when the doubling is actually on the striking surface of the die and all coins struck by that die will show identical features.
To date, no certified examples of a reverse doubled-die 1966 Lincoln cent exist. Mechanical doubling is likely what you see, not a true doubled-die error. Mechanical doubling is the most common type of doubling on U.S. coins and is most often confused with doubled dies, this doubling is extremely common with numerous examples being produced on all denominations every year. It's value is only what someone is willing to pay.
Well, all "dramatic" means is that its easier to see than some doubled dies. Since by nature a doubled die will be the same on all coins that have been struck by that particular die, it doesn't mean that this example of X year's quarter's double die is better than other examples of the same year, merely that the doubling of this particular die variety is easier to see than others. Some coins have dramatic doubled dies such as the 1955 wheat penny doubled die which is easy to see with the naked eye, while others such as the 1943-P nickel doubled die is much harder to see and generally requires magnification to appreciate.
We might call a doubled die coin "double struck" because it was "minted" twice with the same die. This results in a minting error. A date or part of the design can be "repeated" on a coin thus minted. A coin that escapes the quality control screening and makes it out into circulation can be worth some bucks. A link is provided to the Wikipedia article, below. If a coin is a double die as a result of the die itself having an inconsistency it is worth far more than a coin that was simply struck twice.
What do you mean "double faced" you mean like a doubled die error? Or do you mean it has heads on both sides? If it has heads on both sides it is not a mint product but rather a "magician's coin" and is privately made and pretty much worthless. If it is a doubled die error, please provide the year and mint-mark of the coin so we can better identify if it is a known error and how much it is worth.
Many of the coins are valued in price close to $1,500. The exact price of the coin will vary depending upon its condition.