Finding pennies is considered good luck because years ago people thought that finding metal was a gift from the Gods and meant to protect you from evil.

Finding a penny and picking it up is a relatively new spin on an old superstition. Many years ago, people believed that metal was a gift from the gods, given to man for protection against evil. That developed into the notion that metal brings good luck. In fact, this idea is partially represented in the practice of hanging horseshoes over their doorways, wearing charm bracelets, and carrying good luck coins.

The old wives’ tale of putting a penny in the shoe of a woman on her wedding day comes from a Victorian rhyme: "Something old, something new, something borrowed, something blue and a silver sixpence in your shoe." These superstitions were all requests for good luck for the bride. Perhaps because finding a penny was easier than finding a silver sixpence, people made a substitution. Now the saying concludes, "and a lucky penny in the shoe." The penny was intended to be worn in the shoe of the bride to ensure that the newly married couple would always have wealth. The tying of
metal cans behind a newlywed couple’s car is another version of the superstition that metal protects and brings wealth.

The saying, "Put a penny wrapped in paper, keep it to avoid your debtors," is another way that metal was thought to bring wealth.

Finding a penny is still considered good luck, but some variations of the old wives' tale includes the position of the penny. If the penny is found heads up, it brings good luck. If it is found heads down, it brings bad luck. If the finder gives it to a friend, he passes the luck on to someone else.