Have you ever paused to really look at a quarter in your hand? Most of us use coins every day—feeding them into parking meters, tossing them into vending machines, or flipping them to make a quick decision—without noticing the tiny details. But if you run your thumb along the edge of a dime or quarter, you’ll feel something fascinating: a series of small ridges. They may seem decorative, but these grooves are the result of centuries-old battles against fraud, and their story begins with thieves and a brilliant scientist.
Back in the 1600s, coins were made of precious metals like silver and gold. Thieves discovered a way to profit by shaving tiny slivers from the edges—a crime called “coin clipping.” Over time, they could collect enough of these shavings to melt down and sell, while still spending the clipped coins at full value. The practice grew so widespread that it threatened entire economies, forcing governments to find a clever solution. That solution came in 1696, when Sir Isaac Newton, then Warden of the Royal Mint, stepped in.
Newton introduced reeded, or ridged, edges to coins. Suddenly, clipping became obvious—any tampered coin would show uneven or broken ridges. Beyond designing this innovation, Newton personally prosecuted counterfeiters, earning a reputation for protecting the integrity of currency. His efforts restored public trust in money, and his system of ridges proved so effective that it remains in use more than three centuries later.
Today, even though modern quarters and dimes are no longer made from precious metals, the ridges still serve multiple purposes. They help vending machines and banks detect counterfeits, allow the visually impaired to distinguish between coins by touch, and preserve the familiar look and feel of money that people trust. Meanwhile, pennies and nickels remain smooth because they never contained valuable metals to begin with. The next time you hold a coin, take a moment to notice its edge—you’re touching a design born from history, security, and tradition that continues to live in your pocket today.