Interesting side story: for centuries coins were intentionally made to have a ribbed side surface because otherwise people would sand/cut off the sides and sell

Interesting side story: for centuries coins were intentionally made to have a ribbed side surface because otherwise people would sand/cut off the sides and sell the obtained metal. Nowadays coins are usually not made of pure and/or very valuable metals, but the notches have stayed to help impaired people and automatic identification of coins.