Have you ever noticed the regular, jagged lines on the edge of a coin? These serrated lines have a formal name: "edge serrations." Why did designers create these serrations on the coin's edge? Was it for aesthetics? Or to prevent it from slipping from your hand? Actually, it's not that simple. Let me explain.
This edge serration design was originally conceived by the renowned scientist Isaac Newton.
Newton served as the Director General of the Royal Mint from 1686 until his death in 1727.
The coin-making process at the time was as follows: metal was first cut using a horse-powered cutting machine, and then, with the help of craftsmen's eyes and hands, it was shaped into round silver coins and stamped with designs. These coins were called "struck" coins.
The most fatal flaw of these coins was their susceptibility to tampering. The denomination was only marked in the center, with no special markings around the edges. Therefore, some people would secretly cut off a section of the coin before selling it.
To solve this problem, Newton invented the edge serration design. This means that regular engravings are made on the edge of the coin. If someone tries to cut off a part of the coin, they will inevitably damage the edge teeth. This allows ordinary people to easily determine whether a coin has been tampered with by checking if the edge teeth are intact. Thus, it becomes clear that the primary function of the coin's edge teeth is actually anti-counterfeiting.
The minting technology for edge teeth has also been continuously improving. For example, the 5-cent coin with plum blossom design minted in the 1990s had intermittent edge teeth, while the panda silver coins issued annually now have beveled edge teeth, and the zodiac commemorative coins issued a few years ago had beveled edge teeth of varying lengths.
