um... Australian ones?

[SpyOne]

that and the US does have four different dollar coins still in circulation.

Eisenhower dollar (1971–1978)
Anthony dollar (1979–1981; 1999)
Sacagawea dollar (2000–Present)
Presidential Dollar Coin Program (2007–2016?)

For those unfamiliar with US coins, any machine that can take any of the last 3 will take them all: they are exactly the same size. The Susan B. Anthony dollar is silver in color, while the Sacagawea and President versions are gold in color (I've read it is a molebdinum alloy), and differ only in their artwork.
The Eisenhower Dollar is a throwing weapon: it weighs about an ounce (28-30 grams), and is a couple of inches in diameter, and I don't think there has ever been a machine made that accepts them (although slot machines might have been made).

[edible_hat]

Are you in Sydney EH?

Nope, the enlarged country town known as Adelaide.

[TealJellyfish]

The Gold Kind... Goodness Me some people!

Are you in Sydney EH? Cause if you are I am going to start taking extra bloody care crossing the road! THAT PERSON DRIVES!

[Gurndigarn]

y point, though, is still valid. No matter the country, all the commonly occurring dollar coins are as interchangeable with others from the same currency system.

Not in vending machines if they've changed sizes, or sometimes metal content. Which does happen. For instance, the US half-dime was made out of silver and was half the size of a dime for a long time, until they decided that that was just too itty-bitty for practical use (and a silver shortage helped the demise of the half-dime). How often change like this happens depends on country stability, inflation, and stoginess.

The US has made special effort to try to ensure the dollar coins after Ike had similar weights and electromagnetic signatures, otherwise some machines would have rejected whichever one they weren't set up for.

[JustADude]

Look again. The US dollar coins minted since 1979 (Anthony/Sacagawea/Presidential dollars) are much small than the dollar coins minted earlier (Eisenhower dollar). The coins since 1979 are 26.5mm in diameter and weight 8.1 gm. The ones minted earlier are 38.1 mm in diameter and weigh 22.68 to 24.59 gm depending on the composition.

Eisenhower dollar.

Anthony/Sacagawea/Presidential dollars.

My bad. I just assumed because the other three were the same they matched the Eisenhower.

My point, though, is still valid. No matter the country, all the commonly occurring dollar coins are as interchangeable with others from the same currency system.

[Ironclad Alibi]

They do change the design every now and then, but the size and weight is always the same. I've got one somewhere with a special mark on it that indicates I made it by pressing the button on the make-your-own-$1-coin machine at the mint.

Something like that ought to drive collectors crazy a hundred or so years from now.

[edible_hat]

Except EH is in Australia, and I'm not sure, but I don't think they have multiples like that.

They do change the design every now and then, but the size and weight is always the same. I've got one somewhere with a special mark on it that indicates I made it by pressing the button on the make-your-own-$1-coin machine at the mint.

[Ironclad Alibi]

that and the US does have four different dollar coins still in circulation.

Eisenhower dollar (1971–1978)
Anthony dollar (1979–1981; 1999)
Sacagawea dollar (2000–Present)
Presidential Dollar Coin Program (2007–2016?)

It wouldn't matter anyway, if they did, since one of the main requirements of all four variants of the USD $1 coins is that their mass and dimensions be close enough to the Eisenhower to be considered identical by automated devices like vending machines and car-washes.

Look again. The US dollar coins minted since 1979 (Anthony/Sacagawea/Presidential dollars) are much small than the dollar coins minted earlier (Eisenhower dollar). The coins since 1979 are 26.5mm in diameter and weight 8.1 gm. The ones minted earlier are 38.1 mm in diameter and weigh 22.68 to 24.59 gm depending on the composition.

Eisenhower dollar.

Anthony/Sacagawea/Presidential dollars.

[JustADude]

Except EH is in Australia, and I'm not sure, but I don't think they have multiples like that.

It wouldn't matter anyway, if they did, since one of the main requirements of all four variants of the USD $1 coins is that their mass and dimensions be close enough to the Eisenhower to be considered identical by automated devices like vending machines and car-washes.

[Madhatter_67_85]

Australia has $1 & $2 coins. Their paper money doesn't come in anything less than a five note if I remember correctly (been a few years since I went down under). I sure did have some heavy damn pockets after a few days of being there though.

[Broomjockey]

Some amusement parks used to use coins that said "1$" on one side and "not valid anywhere else" on the other. (Riverbend tried that and they went back to their old coinage system)

Oh! You totally reminded me of these "Downtown Dollar" things we had here. I never really found out just what they were for beyond parking and taking the bus, but supposedly they could also be used at some businesses downtown. So some areas do have stuff like that.

[Evil Queen]

Yeah, but tokens are not $1 coins, even if they're worth a buck.

Some amusement parks used to use coins that said "1$" on one side and "not valid anywhere else" on the other. (Riverbend tried that and they went back to their old coinage system)

[Broomjockey]

that and the US does have four different dollar coins still in circulation.

Eisenhower dollar (1971–1978)
Anthony dollar (1979–1981; 1999)
Sacagawea dollar (2000–Present)
Presidential Dollar Coin Program (2007–2016?)

Except EH is in Australia, and I'm not sure, but I don't think they have multiples like that.

[BlaqueKatt]

that and the US does have four different dollar coins still in circulation.

Eisenhower dollar (1971–1978)
Anthony dollar (1979–1981; 1999)
Sacagawea dollar (2000–Present)
Presidential Dollar Coin Program (2007–2016?)

[Samaliel]

Yeah, but tokens are not $1 coins, even if they're worth a buck.