Is This Coin Real? What Is It?

Resizing is not doing what I want. Let's try again.

It certainly looks Spanish (or rather, Spanish-colonial), but certain details are "wrong": the portrait, and the way that, for example, the letter sizes in the word "DEI" are all different, indicate to me that this is actually a contemporary counterfeit. The brassy colour would also lend weight to this theory (it was presumably originally made with a silvery wash, which has since disappeared). Finally, 28mm is a good size for a 2 reales (quarter-dollar), but 4.8 grams is way too light, even for a well-worn example.

American-made counterfeits with the "mintmark" given as "FMR S.I.H" are reported (no genuine 2 reales coin has this legend); Kleeberg in his "Circulating Counterfeits of the Americas" lists this reverse type as number M5.

Contemporary counterfeits are highly collectable artifacts in their own right.

SAP, thank you for researching this. I was not able to find any examples of the FMR.S.I.H mark; which led me to Kleeberg's document. I missed the reference to M5. This is the only image that I've found where the GRATIA letters line up on the bust.

Regards,
Dslobo

As you can see, there are some vestiges of the place where the ring that made it a button was. Here's an different Guaiaca>

.