Coin dealers know their metals, dates, and history, and watching them evaluate a pile of coins that a customer wants to sell for cash can be really interesting. It helps to prepare the coins ahead of time if you want to sell some because that gives the coin dealer more time to concentrate on the coins instead of preparing them themselves. Preparation isn't extensive, and unless you have a lot of coins, it won't take you long to do this.

Don't Clean Them

The first step actually involves avoiding something: cleaning. Sure, if you dripped some water on a coin, wipe that off. But you don't want to put the coins through cleaning processes to remove tarnish, hardened dirt, or other dry materials. The chemicals used in those processes — even seemingly mild ingredients like baking soda — can damage coin finishes. (Baking soda is abrasive and can scratch the surface if you're not careful.) You don't want anything wet dripping off them, but dry corrosion and discoloration should be left alone. If the coin has anything on it that you think should be removed, call the coin dealer and ask them what cleaning process they recommend.

Sort and Separate as Many as You Can

Try to separate the coins into piles of like kind, such as putting all Mercury dimes together, all silver quarters from the 1930s and 1940s together, and those from the 1950s and 1960s together — the older coins may have collectible value as opposed to silver scrap value — and so on. This makes the evaluation process go faster, as it's easier for the coin dealer to see what you have. Put the coins in zippered bags and protective cases, if you have them, so you can keep those collectible coins looking good.

Call Ahead About Foreign Coins

Coin dealers handle foreign in-circulation coins in different ways. These are coins that are currently or were previously used as actual currency for daily spending in other countries, such as the euro or yen, and not special coins minted solely for investment value, such as the gold Canadian maple leaf or gold South African Krugerrand. Some dealers won't look at foreign in-circulation coins unless the coins are gold or silver or if they have a known collectible value. Others will offer a bulk price based on the weight of the pile you have, regardless of country of origin. Yet others may offer foreign currency exchange, in which you can get a small amount of U.S. change based on current exchange rates. Before taking these coins to a dealer, call that dealer to ensure you know how the coins will be treated.

Most metro areas have at least a couple of coin dealers, if not more, so do some comparison shopping for coin sales policies. Find the dealer who will be able to give you the most cash for your rare and precious coins. Contact a coin dealer in your area to learn more.