Have you ever noticed that dimes and quarters have a rough edge while nickels and pennies remain smooth? There’s actually a very clever reason for this!
In the past, coins were stamped from different types of metal cast at a weight that represented the true value of the coin.
One silver dollar was crafted out a single ounce of silver. It wasn’t long until people realized they could shave off pieces of the coin (to sell independently) and still spend the shaven ones – even though they weren’t worth the same amount anymore.
The coin minters got wise to this and added the rigid pattern to the precious coins specifically to make it easy to tell if someone had shaven it.