In 1965, Why Did America Start Making Clad Coins Instead Of Solid Base Metal?

It seems difficult to find an authoritative source, probably because vending machine people don't want their exact secrets known, but from what I've found today it seems like at least some machines have a ferromagnetic device to weed out those counterfeits, and then also read the EM signature which is compared with known good signatures, as well as reading the coin's diameter, and then speed determination on top of that to separate into denomination buckets. Some of them skip the ferromagnetic part and only use EM signature. The difference with what @publius posted above is that these sources are saying that the EM signature is compared against known good ones digitally. Technology they didn't have in 1965 of course.

On the Thai coins, I think only the 2 and 5 baht are clad in the modern era. Similar to US dimes and quarters. The 2 baht also came in nickel-plated steel and copper-aluminium-nickel. The 1 and 10 baht are not clad. I don't think I've ever seen a vending machine in Thailand. My spouse says they've started showing up in the last 5 years or so. So if that wasn't a factor in their coin composition, why did Thailand decide on clad? Maybe banks use a similar technology to sort out fakes.

Do you know what the "concern" was?

Great thread!

I learned a lot!

Great stuff, I've wondered about this topic for decades, a heartfelt thanks to the various posters who filled in details.

Everything and more than you wanted to know about the traditional US payphone except the coin acceptor piece we're worried about here:

http://dougkerr.net/Pumpkin/article...ditional.pdf

and

https://www.smithsonianmag.com/hist...e-180952727/

Huh!

I just discovered that Numista has a section on US telephone tokens and there's a very inactive club on the net for them.

https://en.numista.com/catalogue/in...&ttte=y&p=10

Curiously Numista lists only about 20 different tokens and not all of them are common issues. There are several hundred different Illinois telephone tokens including reorders. There's even one for the World's Fair which for some unknown reason is quite uncommon.

Vending machines and other coin operated machines have been a big part of the US economy for over a century.

Nickelodeons were common back in the 1890's. These were parlors that changed your nickels into amusement tokens which are another very difficult collectible.

I've seen this token. I don't know anything about it if it's the same one I've seen but I classify the cu/ ni version as a modern NJ amusement token because of the name. IMS it says "good for one play" on it.

OK. I found it.

I have three different ones that are incuse and have two grooves on the back. two have the number "16" in the middle and are more common than the version with no number. In aggregate there are 9 tokens from this source. I know little about them except they are modern amusement (arcade) tokens and likely New Jersey. The previous owner of one of them like yours identified one as GBD/ M-UNID but I don't recognize his categorization system.

Alpert and Smith list it in "modern unidentified" as GBD B 23 Sd. There are lots of young people who have been working on these since the days I was in the loop.

There are a lot of opportunities in 20th century tokens and lots and lots of rarities. Entrance costs are nominal and educational opportunities extreme. Most of my collections are for sale. But even acquiring these tokens one at a time is still very easy and inexpensive. Nobody really knows the common issues from the rare.

The mind boggles at the numbers of tokens and clad coins that have been through the machines. Most of those old clad quarters have been through a machine dozens and dozens and dozens of times and through counting machines thousands of times. It's a wonder there are any old clads left in circulation at all since they were designed to last only thirty years. They have greatly exceeded expectations because they are so durable most are lost or destroyed before they have a chance to wear out.