Bullion coins have, at their base, the smelt value of their base metal (e.g. Gold, silver, etc.). Even though we consider Bullion to be Silver or Gold, Copper, Platinum, and Palladium are all used in coins. You also have to consider the purity of the product – 24 karat gold? .999 Silver? Alloys are often hard to spot, unless you use a test kit . (link to Amazon)
Smelt values for US coins can be found here: U.S. Silver Coin Melt Value Calculator – Coinflation
Bullion prices are based on weight (usually ounces or Troy ounces) and subject to are supply and demand, based on market forces.
Many coins are considered “Culls” or rejects because of circulation marks and wear. These can usually be bought at near melt value because they have diminished value as a collectible coin.
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One of my favorite places to buy Bullion coins is eBay, especially if you like Bullion coins with Elvis or Koalas.
US Money, Even Bills, were backed by gold (on the gold Standard), until 1933:
You can purchase Gold certificates on eBay. They are popular collectors items.
Good luck with your bullion – know your values!
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