BUFFALO nickels are extremely popular, but a small detail can distinguish between one worth a few hundred bucks and more than $100,000

These rare nickels were minted by the US from 1913 to 1938. They are sometimes called Indian Head nickels because of the image of a Native American individual on the head side of the coin. The tail side of the coin has a buffalo.

A die break, also known as a cud, is an error on a coin that is formed when a die, (a metallic piece that is used to strike a coin) is missing a piece near the rim.

When dies strike coins, they have a heavy impact and pressure and the metal from the blank part of the coin, known as the planchet, overlaps the area left by the missing piece of the die.

Coins with such deformities are rare thanks to the strict quality control measures at the US Mint.

When such errors do occur, they are often caught and destroyed.

However, those that slip through the net become huge collector's items worth much more than their face value.

An error at the Denver mint led to thousands of nickels being minted, and the buffalo was missing one of its legs.

"The 1937-D 3 Legs variety resulted from over-zealous polishing of a worn reverse die. The front foreleg was almost completely removed, and the back leg developed a "moth-eaten" appearance," said Ron Guth from PCGS.

Unfortunately, thousands of the coins entered circulation before the mistake was caught.

"The 1937-D "three-legged" Buffalo nickel is one of the most famous and most important coins of the 20th century. It is arguably the classic Buffalo nickel," added David Hall, co-founder of PCGS.

Only 10,000 have survived to this day.