The world's greatest coin expert, John Mercanti Coins is responsible for preserving the oldest and most valuable coins in the world. There is no doubt that this man knows his stuff when it comes to gold, silver, platinum, and bronze coins. There are many reasons why you should use his coin guide. If you love coins then you need to get a copy of his book. In this book, you will find all the information you need to know about preserving your collection or selling your collection.