Here's a crusty old 1738 8 reales from a mixed lot I just received. Wondering about its authenticity. I don't have weight or diameter figures but can get them tomorrow. Thanks!
I'm leaning towards authentic and that it was quite likely recovered from a shipwreck or otherwise found at sea. The cleaning done to it was a bit rough but considering its likely origins I think it's a nice piece overall.
From what I can tell, the legend and other elements line up with some certified pieces I compared it with. I agree that the damage/corrosion appears to be of the "shipwreck effect" variety. What is an acceptable range for weight?
This thread has some very good information about weight tolerances of these coins: https://www.cointalk.com/threads/weight-range-for-spanish-8-reales.238204/. Posts #4 and #14 are especially informative. 27.2638 grams was the maximum weight tolerance for them while 26.8646 grams was the minimum but you can likely expect yours to weigh less than this range. How much less will be hard to say until it is weighed.
I'm sorry to say that without a COA from the shipwreck salvager or conservation company, coins with this type of appearance are nearly impossible to authenticate. The problem is modern fakes of these are common, so what's to stop someone from treating one of those with acid to make it look like it came from a shipwreck? At least check to see if the edge looks correct and try to determine if it's made of silver.
Yeah, that sorta looks right. What can you do to test the silver content? Unfortunately, I cannot quote a post from another thread. Look here for a great edge photo of a potentially similar, undamaged coin.
I think you're overthinking this a bit. COA's can be forged and made up like anything else. In the year 2000, I was given a Spanish silver cob coin (I believe four reales- it is just a bit smaller than a modern half dollar) from a galleon that sank in the 1650's. The friend who gave it to me attests that his father recovered it from having dived to the ship. Now, I expect that the coin is not worth much as it has suffered extensive salt water damage, completely obliterating the design on one side of the coin. At any rate, I do not have any formal COA to accompany the coin but I have no reason to doubt its authenticity or provenance. So sure, the coin in question for this thread could be fake but let's take a step back. Would a counterfeiter really go through the trouble to forge the coin in question, apply acid and then crudely clean it to make it look like a shipwreck coin when doing so would negate any real or potential value that the coin would have had? Perhaps, but I doubt it. Conducting a silver ring test (discussed below) and matching up other characteristics to known genuine examples should be satisfactory in establishing authenticity on a cool but otherwise low-value coin. I would do the silver ring drop test on a preferably wooden table. I'd listen for the characteristic high pitched ringing sound that emanates from silver coins. If it passes this test, I'd be satisfied about its silver content. Just to note, this is not a test I'd recommend on a high-grade piece. Even though it has some cool history to it, realistically the coin is worth little more than bullion value.
Hey I got the quote from the other thread to show up! That's fine for you but what about the next person to buy it? There are many examples of COAs that people do put some faith in. A good example is the El Cazador coins in NGC slabs. Yes, modern processes allow them to be cheaply made from base metal and the shipwreck appearance can hide otherwise obvious markers of a forgery. Do I have proof that this happens? No, but there really is a big problem with forgeries and it just seems to be an obvious way to sell one. Authenticating an 8 reales without surface damage is extremely difficult as it is. Take a look at this thread to see what I mean.
I’ll get an accurate weight today when I am at work. The chemistry lab has all sorts of scales, plumbobs and doohickeys I can use.
Get the chem teacher (or some smart AP Chem student) to show you how to do a specific gravity test assuming they have a scale set up for it. Just make sure air bubbles don't stick to the rough surfaces
Well, the digital scale measured 24.49g which is outside of the tolerance range but not outrageously so. I’ll consult the chem-nerds for specific gravity figures. We English nerds can’t do such things unassisted.
I see nothing on this coin to make me think it might be a fake. But here's how I look at coins like these. First of all they have little to no value to speak of. Yeah, some people who really like the shipwreck genre pay up for them, but in reality they are only doing that because of their own personal preferences - not because the value is justified. Secondly, you can do every test there is and the results will still not be proof that the coin is genuine. This is because many of the counterfeiters use silver of the correct fineness, so even the fakes will still test as being genuine with acid tests, specific gravity, weight, dimensions, etc etc. Point being, even if you do all the test you still don't know any more than you did before doing them. Once you know that much you have to ask yourself - why bother ? If you like the coin, fine, keep it. If you don't then give it away, sell it, trade it. But if you do you should tell others what I have said above.
Thanks for the input as to the authenticity of the coin. I have no intention of selling the coin but want to authenticate it (as best I can given my resources, etc) for the sake of education and knowledge. The coin will ultimately become part of my son’s collection. Last night, at bedtime, I was talking to him about the coin and he immediately perked up. His first response was “those are pictured in my red book and I’ve always wanted one.” I then told him about the possibility that it was a “shipwreck” coin...his eyes widened considerably. Then he said, “what do you plan to do with it...do you think I could do something to earn it?” He’s a good kid who loves coins and is the reason I got into the hobby. I’ll share all the educational details of authenticating the coin with him and he will eat it up. He’s been earning the coin his whole life by being a good kid, but I’ll probably make him sweat a little bit just because...though report cards come out today, so maybe it’ll be his sooner than later. As always, thanks so much CT for all the support!
