1786 MO 8 Reales - Is This A Good Candidate For NCS Or Not?

I've seen a couple 1782s pop up over the last little while as well. There is a cynic in me that doubts the story and the legitimacy of the coins. The toning and wear all kind of looked the same to me, which was a red flag.

There is something in the loop of the D in Dei and something in front of his lips and nose. They kinda look like bubbles, can you get a closeup?

One of the key things I look for is the orientation of the denticles at the rim. They all should be aligned radially on genuine coins. If they are misaligned with the orientation of the nearest letter uprights in the legends, then I might pass on the purchase. Some counterfeits have denticles running askew. How do they look in person on this coin? The orientation of the images makes it difficult to fully assess.

Continuing my investigations, while waiting for the coin to arrive, I checked the seller's selling history. He specializes in older coins (17th-19th centuries)and has sold a good number of 8 reales in the past with positive feedback. That makes me feel more optimistic this coin is authentic.

The coin shows light surface corrosion on most of the coin. Conserved or not it will be a details coin. They MAY be able to lighten the color, but what it will look like afterward is impossible to say.

I have received the coin. Here are my photos taken in sunlight.





Under magnification, the rough spots appear to be the black patina/encrustations/dirt over the coin's surfaces. I put it in acetone for a couple of minutes and it came out looking like this with no scrubbing, just a simple acetone soak.




While my stupid side says, "Just put it in lemon juice!" I won't listen to that part of my brain. I'll leave it as is, study it some more and then decide if I want to send it to NCS. I don't think the coin is corroded and that the mottled areas are the black patina, from being buried for 230 years, over the silver surfaces. The reverse surfaces look to be in good shape.

I also purchased this 1779 8 Reales from the Lima, Peru mint which was part of the same hoard. This coin looks to be in very nice shape under the black patina/encrustations/dirt. It might well receive a "details" slab, but it certainly looks nice.