Why Do Coins Have Ridges?

iStock/tweetyclaw
iStock/tweetyclaw

The stylish rims you might have noticed on U.S. dimes, quarters, half dollars and some dollar coins are called reeded edges. They’ve been on American currency almost since day one as a way of keeping people honest.

The United States Mint built its first minting facility in Philadelphia in 1792. The following March, it produced its first batch of circulating coins - 11,178 copper pennies. The silver coins that soon followed were linked to a silver standard, per the 1792 Mint and Coinage Act. This meant the “major” coins were at least partially made up of the precious metal (the first dollar coin, from 1794, was 89.25% silver and 10.75% copper). Silver dollars contained about a dollar’s worth of silver, give or take, and the others – half dollars, quarters and dimes – had a proportionate metallic content and size. Half-dollar coins contained ½ the amount of silver as a dollar and were half the size, quarters had ¼ the amount of silver, and so on.

Reeded edges served a two-fold security purpose for silver coins. One, they added an additional, intricate element to the coins that made them more difficult to counterfeit. Two, they prevented fraud.

How do ridges prevent fraud?

For as long as coins have been made from precious metal, a fairly common way to make a quick, ill-gotten buck was coin clipping. Clippers would shave off a tiny amount of metal all the way around the rims of a bunch of coins, collect the shavings, then sell them. Working carefully, a coin clipper could trim enough off of coins to make a nice profit, but not so much as to make them noticeably lighter or smaller. A clipper could then still go out and spend his devalued coins as if they were unaltered. Reeded edges ruined this scheme, since a shaved edge would be immediately obvious and alert anyone who received one that something was wrong.

Why don't nickels and pennies have reeded edges? Nickels and pennies are mainly composed of inexpensive metals, so the chances that they would be tampered with are low.

Before their adoption by the U.S. Mint, reeded edges were also used in the UK. When the physicist Isaac Newton became warden of the Royal Mint in 1696, he used reeded edges, among other means, to combat clippers and counterfeiters. Other European coins from as far back as the early 1500s also feature reeded edges.

Wait, are people still clipping coins?

Due to the abandonment of the silver standard and a worldwide silver shortage in the mid-20th century, the Coinage Act of 1965 authorized a change in the composition of dimes, quarters, and half-dollars, gradually shrinking their silver content down to the present-day 0%. Coin clipping is no longer a problem, but reeded edges are still around, a centuries-old security measure hanging on in an age where people pay for things with their smart phones instead of digging out pocket change. The tenacity is admirable. But why are they still there?

Coins are made by stamping coin blanks with a metal tool called a die. The die is engraved with the negative of a coin’s design, and the positive image is transferred to the coin when stamped. When the coins are struck, a part of the die called the collar holds the blank in place and applies the edge. When the silverless coins were first produced, the government didn’t see any need to make or buy expensive new dies or collars. Keeping the reeding wouldn’t hurt anyone, they figured, so the new coins were struck from the same old dies as the old ones, and reeding continued to be used as a matter of tradition and backwards-compatibility. Newer coins with updated designs (state quarters, new portraits) also have reeded edges. The design element lived to see another day on the new dies because reeding is useful for distinguishing coins by feel as well as appearance, making them more user-friendly for the visually impaired.

I can't stand the suspense. How many ridges are on my quarter?

If you gather up a bunch of coins, you'll see that not all reeded edges are created equal. The number and size of reeds on coins is not dictated by law, so individual U.S. Mints were long free to make their reeds to their own in-house specifications, leading to distinct style differences between coins from different mints and eras. Rare dimes from the now-defunct Carson City Mint’s 1871-74 runs, for example, have 89 broad, widely spaced reeds. The dimes made by the Philadelphia Mint in those same years have 113 thin, tightly-spaced reeds. 

Things are a little more standardized now and the Mint lists its reeding specifications as follows: dimes, 118; quarters, 119; half dollars, 150; dollar, 198; Susan B. Anthony dollar, 133.

Keep Your Cat Busy With a Board Game That Doubles as a Scratch Pad

Cheerble
Cheerble

No matter how much you love playing with your cat, waving a feather toy in front of its face can get monotonous after a while (for the both of you). To shake up playtime, the Cheerble three-in-one board game looks to provide your feline housemate with hours of hands-free entertainment.

Cheerble's board game, which is currently raising money on Kickstarter, is designed to keep even the most restless cats stimulated. The first component of the game is the electronic Cheerble ball, which rolls on its own when your cat touches it with their paw or nose—no remote control required. And on days when your cat is especially energetic, you can adjust the ball's settings to roll and bounce in a way that matches their stamina.

Cheerable cat toy on Kickstarter.
Cheerble

The Cheerble balls are meant to pair with the Cheerble game board, which consists of a box that has plenty of room for balls to roll around. The board is also covered on one side with a platform that has holes big enough for your cat to fit their paws through, so they can hunt the balls like a game of Whack-a-Mole. And if your cat ever loses interest in chasing the ball, the board also includes a built-in scratch pad and fluffy wand toy to slap around. A simplified version of the board game includes the scratch pad without the wand or hole maze, so you can tailor your purchase for your cat's interests.

Cheerble cat board game.
Cheerble

Since launching its campaign on Kickstarter on April 23, Cheerble has raised over $128,000, already blowing past its initial goal of $6416. You can back the Kickstarter today to claim a Cheerble product, with $32 getting you a ball and $58 getting you the board game. You can make your pledge here, with shipping estimated for July 2020.

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Why Did Noon Used to Mean 3 p.m.?

3 p.m. is basically noon for people who wake up at 12 p.m.
3 p.m. is basically noon for people who wake up at 12 p.m.
Mckyartstudio/iStock via Getty Images

If you’re a late sleeper, you might find yourself thinking 12 p.m. seems way too early to be considered midday, and the word noon would much better describe, say, 3 p.m. It turns out that ancient Romans would have agreed with you, if only for etymological reasons.

As Reader’s Digest explains, the days in ancient Rome were split into four periods of three hours each. The first hour was at sunrise around 6 a.m.—called prime, for first—followed by 9 a.m. (terce, denoting the third hour), 12 p.m. (sext, for sixth), and 3 p.m. (none, for ninth).

According to Merriam-Webster, Middle and Old English borrowed the time-keeping tradition, along with the Latin word for ninth, which was changed to nōn and eventually noon. Though we’re not sure exactly when or why noon started referring to 12 p.m. instead of 3 p.m., it could have something to do with Christian prayer traditions. In the Bible, Jesus’s crucifixion is said to have taken place at the ninth hour, and that’s when worshippers partook in their second of three daily prayers; the others were in the morning and evening. It’s possible that hungry monks were behind noon’s gradual shift from 3 p.m. to 12 p.m.—since their daily fast didn’t end until after the midday prayer, they had a built-in motive for moving it earlier.

While we didn’t exactly stay true to the original Latin meaning of noon, there’s another important remnant of ancient Rome hiding in the way we tell time today. Romans referred to 12 p.m. as meridiem, for midday, and so do we. A.M. is an abbreviation for ante meridiem, or before midday, and P.M. means post meridiem, or after midday.

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