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.

In What Field Was Dr. Martin Luther King Jr. a Doctor?

Express Newspapers/Getty Images
Express Newspapers/Getty Images

Martin Luther King Jr. earned a doctorate in systematic theology from Boston University in 1955. He’d previously earned a Bachelor of Arts from Morehouse College and a Bachelor of Divinity from Crozer Theological Seminary. His dissertation, “A Comparison of the Conception of God in the Thinking of Paul Tillich and Henry Nelson Wieman,” examined the two religious philosophers’ views of God in comparison to each other, and to King’s own concept of a "knowable and personal" God.

In 1989, some three decades after King had earned his doctorate, archivists working with The Martin Luther King Papers Project discovered that King’s dissertation suffered from what they called a “problematic use of sources.” King, they learned, had taken a large amount of material verbatim from other scholars and sources and used it in his work without full or proper attribution, and sometimes no attribution at all.

In 1991, a Boston University investigatory committee concluded that King had indeed plagiarized parts of his dissertation, but found that it was “impractical to reach, on the available evidence, any conclusions about Dr. King's reasons for failing to attribute some, but not all, of his sources.” That is, it could have been anything from malicious intent to simple forgetfulness—no one can determine for sure today. They did not recommend a posthumous revocation of his degree, but instead suggested that a letter be attached to the dissertation in the university library noting the passages lacked quotations and citations.

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Who Is 'The Real McCoy'?

Inventor Elijah McCoy is may or may not be "The Real McCoy."
Inventor Elijah McCoy is may or may not be "The Real McCoy."
Ypsilanti Historical Society, CC BY-SA 4.0 via Wikimedia Commons

After taking a cool, carbonated sip of champagne from the Champagne region of France, you might say, “Ah, now that’s the real McCoy.” Sparkling wine from anywhere else is technically just sparkling wine.

The phrase “the real McCoy,” which can be used to describe any genuine version of something, has several possible origin stories. And while none of them mention champagne, a few do involve other types of alcohol.

According to HowStuffWorks, the earliest known recorded instance of the saying was an 1856 reference to whisky in the Scottish National Dictionary—"A drappie [drop] o' the real MacKay”—and by 1870, a pair of whisky distillers by the name of McKay had adopted the slogan “the real McKay” for their products. As the theory goes, the phrase made its long journey across the pond, where it eventually evolved into the Americanized “McCoy.”

Another theory suggests “the real McCoy” originated in the United States during Prohibition. In 1920, Florida-based rum runner Bill McCoy was the first enterprising individual to stock a ship with alcohol in the Caribbean, sail to New York, and idle at least three miles offshore, where he could sell his wares legally in what was then considered international waters. Since McCoy didn’t water down his alcohol with substances like prune juice, wood alcohol, and even turpentine, people believe his customers started calling his top-notch product “the real McCoy.” There’s no definitive proof that this origin story is true, but The Real McCoy rum distillery was founded on the notion.

There are also a couple other leading theories that have nothing to do with alcohol. In 1872, inventor Elijah McCoy patented a self-regulating machine that lubricated parts of a steam engine without the need for manual maintenance, allowing trains to run continuously for much longer distances. According to Snopes, the invention’s success spawned a plethora of poor-quality imitations, which led railroad personnel to refer to McCoy’s machines as “the real McCoy.”

Elijah McCoy’s invention modernized the transportation industry, but he wasn’t the only 19th-century McCoy who packed a punch. The other was welterweight champion Norman Selby, better known as Kid McCoy. In one story, McCoy decked a drunken bar patron to prove that he really was the famous boxer, prompting others to christen him “the real McCoy.” In another, his alleged penchant for throwing fights caused the press to start calling him “the real McCoy” to acknowledge when he was actually trying to win. And yet another simply suggests that the boxer’s popularity birthed so many McCoy-wannabes that Selby started to specify that he was, in fact, the real McCoy.

So which “the real McCoy” origin story is the real McCoy? The 1856 Scottish mention of “the real MacKay” came before Elijah McCoy’s railroad invention, Kid McCoy’s boxing career, and Bill McCoy’s rum-running escapades, but it’s possible that the phrase just gained popularity in different spheres at different times.

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