If you collect old coins, you likely have several that are showing their age. Historic coins are typically discolored, but that doesn’t mean they should be cleaned. You should never clean your collection if you want to retain its value.

The Value of Patina

Over time, metal coins take on brown or green colorations. This patina is the metal’s natural method of protecting itself from the elements. To collectors, a patina isn’t a drawback or sign of worthlessness. Old coins with a natural patina—which might be brown on copper, gray on silver or nickel, or warm yellow on gold—are typically more valuable than those that are bright and shiny. 

The Effect of Cleaning on Old Coins

When collectors and experts evaluate old coins, their condition is one of the primary factors in determining their worth. A coin that’s been cleaned, no matter its age or rarity, is likely to be disqualified from grading. 

A coin’s patina is often closely tied to its age and seen as desirable. Cleaning with harsh or abrasive cleaners not only removes the patina but can also do irreparable damage to the metal surface. Even if the damage isn’t visible to the naked eye, it still reduces the coin’s value. Therefore, cleaning can affect a coin’s monetary and historical value. 

If you’re wondering about the value of your old coins, turn to the experts at Hawaiian Islands Stamp & Coin in Honolulu. For almost 50 years, these trusted collectors have bought and sold gold, silver, and collectibles. They’ll perform a professional and thorough valuation of your collection and pay cash if you decide to sell. They can also provide guidance on how to care for your collection to retain its value. Call (808) 531-6251 to make an appointment, or visit them online for more information on their services.