Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Proof coinage means special early samples of a coin issue, historically made for checking the dies and for archival purposes, but nowadays often struck in greater numbers specially for coin collectors (numismatists). Many countries now issue them. Preparation of a proof striking usually involved polishing of the dies. They can usually be distinguished from normal circulation coins by their sharper rims and design, as well as much smoother "fields" - the blank areas not part of the coin's design. The dies for making modern proof coins are often treated with chemicals to make certain parts of the design take on a frosted appearance, with the polished fields taking on a mirror finish. Several other methods have been used in the past to achieve this effect, including sand blasting the dies, and matte proofs. Proof coins of the early 19th century even appear to be scratched, but it was part of the production process.

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