![]() ![]() ![]() When heat and light act upon PVC it breaks down chemically and hydrochloric acid is released. To make them flexible manufacturers often blend plasticizers in with the material, and all this spells trouble for coin collectors. The primary villain is a chemical compound called polyvinyl chloride, usually referred to as simply ''PVC.'' This substance is widely used in 2-by-2 flips - coin album pages and currency holders. Many of the coin holders in common use today -particularly the vinyl ''flips'' - have chemical ingredients which react with the surfaces of the coins, often causing permanent damage. The problem can be summed up in a single word - corrosion. But, as coin collectors are learning, little things can also do a lot of harm: for instance, many coins worth thousands of dollars are being ruined these days by plastic holders worth only two or three cents. Little things can often do a lot of good - for example, New York City recently escaped a potentially major tragedy when a small 15-cent hardware item helped keep a propane tank truck from exploding. ![]()
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