This is part of why coin edges were milled or reeded:
The ridges made it harder to counterfeit the coins, and it also made clipping or filing of the edges to collect some of the gold or silver very obvious. In Britain this was implemented by everybody’s favorite scientist:
Some gold and silver coins were reeded to discourage clipping, i.e. scraping off the precious metals from the edge of the coin, to maintain its stated value in precious metal. This practice was made more difficult through the implementation of reeding by Isaac Newton in 1698, during his time as warden of the Royal Mint.
It’s less relevant today, as few coins are minted with precious metals, though the varied edges also help people with visual impairments to identify different denominations by feel.
This is part of why coin edges were milled or reeded:
The ridges made it harder to counterfeit the coins, and it also made clipping or filing of the edges to collect some of the gold or silver very obvious. In Britain this was implemented by everybody’s favorite scientist:
It’s less relevant today, as few coins are minted with precious metals, though the varied edges also help people with visual impairments to identify different denominations by feel.