High Relief Gold Coins and Proof Gold Coins appeal to serious collectors as well as to those looking to invest in premium products that are almost guaranteed to increase in value. High Relief Gold Coins were first produced in Ancient Greece and are exactly as described – intricate designs are struck hundreds of times with a die to create an image that is higher than the coin's edge. 'Proof' signifies that the coin is extensively polished to create a gleaming background. Details are clearer and more defined and collectors have likened owning High Relief and Proof Gold Coins to owning a small, very beautiful sculpture. These superior quality gold coins tend to have a millesimal fineness of .9999 and are often available in very limited numbers.