This is an interesting coin!!!! It's a Netherlands Overijssel 1733 ducaton. It is actually a shipwreck coin from the ship Vliegent Hart("Flying Deer"), a Dutch East Indies vessel, which sank on 3rd February 1735. It had just departed Rammekens for the East Indies when the deadly combination of a northeast gale, a spring tide and pilot error sent her into a sand bank behind her sister-ship Anna Catharina. The latter ship broke apart in the storm while the Vliegent Hart, damaged and firing her cannons in distress, slipped off the bank and sank in 10 fathoms(~20m of water), with all hands. the wreck was discovered in 1981, and eventually 3 chests of Mexican Silver and Dutch gold were recovered. (67,000 pieces). There were also many 8 Real Spanish cobbs. These ducatons were actually contraband carried by the crew, to use in the East Indies for their own profit. I'm not sure how many Ducatons there were, but the coins seem to have been in various states of corrosion. this one has some corrosion along one edge. Strangely enough, I picked this up in a well known annual Japanese antique market in Tokyo. I don't think the vendor knew what it was, as he had a lot of other goods, along with a mixed collection of coins. The Japanese coins were about the expected price, but the world coins were all cheap. The hinge on the case was broken, so it was a discounted price. Cost was 4000yen, or around $36 / 30 EUR Link to another example: https://www.coinfactswiki.com/wiki/File:Overijssel_Sed21-565.jpg
Wow if another one sold for over $400 at auction, it looks like you did pretty well for $36! Very nice coin and a cool story behind it.
This is one I would call on @GDJMSP or well seems pretty well up his alley. Interesting coin, looks like a lot of original luster on that piece, But know zero about it.
It seems you know most of what there is to know regarding the history of the coin. About the only comment I would make is that there is a good bit of corrosion, which is of course to be expected on silver shipwreck coins. But combined with the case it's definitely a nice collectible. I would recommend it not be stored in the case however, and that the case not be stored anywhere around any of your coins as wood puts off gasses harmful to coins. And there is no sense in allowing the coin to suffer any more damage than it already has.
I was actually thinking about getting it graded and slabbed by NGC. I can modify the case inside to fit the slab.
You can try and get it graded if you like, but it could go either either way as sometimes they will cleanly grade shipwreck coins when if it were not a shipwreck coin they would never cleanly grade it - because it's corroded. But if you do you definitely do not want to store the slab in that case ! Slabs are not airtight and the gasses put off by the wood are definitely harmful to coins.
Thought I'd tag on and post mine, though it's not in great shape. It's also a shipwreck coin, from the Dutch East-Indiaman Hollandia, sunk in 1743.
