Some coins have ridges on their edges and others are smooth. The ridges are put there for a variety of reasons.
Deterring counterfeiting: The process of counterfeiting coins involves creating a fake coin that is indistinguishable from a genuine one. This can be done by altering the design of an existing coin, or by creating a new coin from scratch. Either way, the goal is to produce a coin that looks and feels genuine, and that can be passed off as such. By adding ridges to the edge of a coin, authorities can make it more difficult for counterfeiters to alter or create convincing fakes. The ridges provide a physical barrier that can be difficult to replicate accurately, and they also create additional surface area that is more difficult to modify without leaving evidence of tampering.
Improving handling and stacking: Coins can be difficult to handle and stack due to their small size and smooth surfaces. This can be especially true for coins that are made of precious metals, which are often very soft and prone to scratching and tarnishing. By adding ridges to the edges of coins, authorities can make them easier to grip and handle, and also make it easier to stack them neatly without them slipping or falling over. This can be particularly useful in settings where coins are handled frequently, such as in banks, casinos, and vending machines.
Decorative purposes: Finally, some coins have ridges on their edges simply for decorative purposes. The ridges can be used to incorporate patterns or symbols that are meaningful to the issuing authority or to the intended audience of the coin. For example, a coin might have ridges that spell out a motto, or that depict a historical or cultural symbol. The ridges can also simply add visual interest to the coin, making it more appealing to collectors or to the public. To learn more about this great hobby, read Quick Guide to Coin Collecting, 2nd Edition.
