Tiny Dime

In my pocket change, I found a 2001-D US dime that is 17mm, rather than the standard 17.91mm. It is not silver. I’ve posted pics with a standard dime for context. 

I suspect it was struck on a foreign planchet. Any idea which country? 

Probably a magician's coin

I have one too.

I made it in my basement this morning.  I suspect yours is just a “washing machine” coin.  Look at the worn and rounded off edge.

I’ve considered that and it brings up a couple of questions:

Would it be perfectly circular if it was a “washing machine” thing?

would there be more wear on the surface features? 

I‘m certainly no expert, but it looks like it would grade around the mid AU range. 

Yes, good points. Typically the faces would show wear but it's possible depending on which machine (not necessarily a washing machine) and how it was stuck in it might only wear on the edges.  They many times end up circular as they rotate freely so no side wears preferentially. Here's one of mine being worn for a very longtime, basically circular and little face wear.

Another problem with your foreign planchet assumption is finding a suitable planchet in use at the same time and made at the Denver mint. Basically they are nonexistent.  Here a list of world coins made between 1991 and 2003 with a 17+/- 0.5 mm diameter, 2.0 +/- 0.5 g weight (based on my small coin).  Many are magnetic and can be eliminated and none were made at US Mints.  Another problem is that the rim is put on first before striking the coin.  The equipment that does this operation won't work properly on an undersized planchet. The rim your coins seems to have is just the edge material being pushed up and over the faces.

I could be wrong but I don't think so.

Thanks for that list of foreign planchets. I’ve been trying to figure out the right words to google it. I’m grateful for the lift!