Typically, gold coins come in sizes that include 1-ounce, ½ oz, ¼ oz, and 1/20 oz. In comparison to common U.S. coins, a 1 ounce bullion coin is similar to the size of a half dollar, and a 1/10 ounce coin is about the size of a dime.
Most of the countries that mint gold have a design that stays the same each year. Some vary the designs annually and date the gold coin, such as the Chinese Panda coins. Proof (PF) uncirculated coins are typically more expensive than non-proof gold coins. They require extra time and effort to make and can have a slightly higher value than non-proof because of demand from collectors. However, both contain the same amount of precious metal so investing in proof coins is highly speculative and generally a play on collectible value as opposed to the metal itself.
Gold coins are produced at a mint by two dies that strike a blank piece of metal with great force. One die as the obverse (front) design for the coin and the other has the reverse (back) design. Proof coins are struck two times or more by the die, while bullion coins are struck once. Gold bullion coins usually have a fineness of .999, which is 24 karats.
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