How do I know this? Because I know a "secret" that apparently every coin minter in the US either doesn't know or ignores: It's too close to the size and feel of a quarter.
The Mint is making sure the coins, which are golden in color and slightly larger and thicker than a quarter, will be widely available.
Why did the Susan B. Anthony and the Sacagawea dollar coins fail? Well, according to mint experts, it was because it didn't have an interesting picture.
Do we really need to be wasting our time and expertise on minting coins with pretty pictures? Shouldn't we be requiring that coin collectors pony up for the expense of generating new coins if its really that important to them?
Look, if you insist on making a new dollar coin, you're gonna have to make it a truly unique size. You damn-well DO NOT make it almost indistinguishable from a lower-denomination coin. If there ain't any more "good" coin sizes avaible, then DON'T MAKE IT.
If you're gonna make new coins, you might as well explore how to make them as light as possible. Again, no one wants to be carrying around a pocket full of dollar coins. Anyone who uses the stamp machines at the USPS can attest to this.
It should also tell you something when the only people that use dollar coins are the USPS vending machines... and only for dispensing change at that.
Bye, bye dollar coin... again.