Expert: Brad Swain - 11/25/2009

Question
Brad,
I have quite a number of old British pennies.  Because of their age, they are covered with years of dirt and grime.  Would I be diminishing the value of the coins if I chose to clean them with copper cleaner, or other cleaning agents?

I look forward to your response.

Thank you,

Bill

Answer
Hi Bill, Cleaning coins that leaves them shiny or scratched, even if only by looking with a magnifying glass, will reduce a coin's value by at least half.
Collector value of a coin depends on date, denomination, mint mark (if any), number minted and condition of a coin, including amount of wear, any dents, scratches or cleaning as well as collector demand for it.
You might also try a library for a copy of the Standard Catalog of World Coins for pictures, values and lots more interesting info.
Brad