A precious coin is one that is very limited and usually made of a precious metal. Gold, silver, platinum and palladium coins are the metals that make precious coins. Gold coins are especially sought after as gold has been a medium of exchange since time immemorial. This means one can get rare gold coins that date back to the times of ancient Greeks. These of course are extremely rare and ask for thousands of dollars or hundreds of thousands.
The value of a precious coin is mostly dependent on its rarity. While precious metals have been around since the earth’s making, the art of minting coins is just a few thousands years old. Coins that date back to the era BC fetch high prices because they are very rare but not they are made of precious metals. A rare silver coin will also be of more value than a gold coin that can be easily found.
Another way of assessing the value of precious coins is by the amount of precious metal in it by weight. Some gold coins are pure 24 karat content while some are only 18 karat in content. This will make the former pricier. This will apply to other precious metals too. A Morgan silver dollar for example has 0.77 troy ounces of silver in it. This makes it more valuable than silver coins of lesser weight in silver may they be a few years ahead in minting. The weight of a precious coin is valuable as the metal can always be recovered.