Fool's gold is an inferior mineral called pyrite that mimics the look of gold.
Pyrite may be shiny and brass-colored, but any miner will tell you, it is not as good as gold.
The inferior mineral nicknamed fool’s gold only mimics gold in looks. Pyrite is more common, harder, and more brittle than gold. When crushed into powder, it looks greenish-black, whereas real gold powder is yellow.
Pyrite contains sulfur and iron. During World War II it was mined to produce sulfuric acid, an industrial chemical. Today, it is used in car batteries, appliances, jewelry, and machinery.
Although fool’s gold can be a disappointing find, it is often discovered near sources of copper and gold . A miner who stops digging once they have a piece of pyrite in hand is the real fool.