It is not always easy to determine how valuable a coin is by looking at it. Some coins are valuable because they are rare. Other coins are valuable because they are in pristine condition. Some very ordinary coins can be worth quite a bit of money. The key to knowing what valuable coins look like is being able to determine the exact type of coin you are dealing with.
It is essential to identify coins accurately to determine whether they are valuable. All this information is on the coin. Important identification information is country of origin, denomination, year and mint mark.
A coin in any condition will be valuable if it is rare. Coins can be rare because very few of them were minted or because very few of them are still around. Once you have identified the coin, a simple search of a coin price book or coin price website will show you if the coin is rare.
Many valuable coins are worth a lot of money because they are rare varieties of common coins. These coins will have a visible error on them that can be easily seen if you know what to look for. Famous examples of this are the 1937-D three legged buffalo nickel and the 1982 Roosevelt dime without a mint mark.
The better the condition of a coin, the more valuable it is. Extremely high-grade uncirculated coins sell for much more than face valuable. Even common date coins can be valuable in ultra-high grades. These coins look very shiny with a frosty appearance and have extremely high detail in the design. It is very important not to touch these coins with your naked fingers or rub them against anything. This will erode their value.
Age is not always an indicator of the value of a coin. Some coins dating back to Roman times are quite inexpensive, while a relatively new coin can be valuable. However, age can indicate whether a coin contains precious metals. Dime, quarter, half dollar and dollar coins minted by the United States before 1964 contain 90 percent silver. The United States also minted 22-karat gold coins before 1933. Modern coins do not contain precious metals.