Coins often have milled edges, a ridged pattern originally meant to reveal clipped metal.

The longer version

When coins were made of precious metal, people shaved slivers from the rim and passed the coin on at full value. Ridged edges were the answer: a pattern cut around the circumference makes missing metal obvious at a glance, because a clipped coin no longer carries the marks all the way round. Clipping was treated as a serious crime.

Once coins were struck in base metals the anti-clipping purpose faded, but the ridging stayed, largely as a signal of genuine striking and as a habit of design. Many modern coins keep reeded edges even though their metal is worth far less than the face value, while others use plain edges or edge inscriptions instead, so the pattern is no longer a reliable guide.

Where this entry sits

Odd Little Things looks at the ordinary objects people touch every day and the small mechanisms and histories hiding inside them. Buttons, zips, pencils, mirrors, stairs, stamps, packaging, and road signs all get their turn. The full list sits on the Odd Little Things page, where every entry is listed in order.