Another NEWP, and medal/exonumia guru advice (conservation question)

Discussion in 'World Coins' started by Stork, Jul 10, 2019.

  1. Stork

    Stork I deliver Supporter

    Cross posting with another forum to enhance responses. This is a recent NEWP, a 1759 medal for the Battle of Belleisle. combo e3e3e3.jpg

    Among my favored themes are mythological beasties and the hippocamp is one of my top favorites. This is a medal I've been on the lookout for for a long time. It's not is superb condition, but good enough for me, though I surely spent too much money chasing it. Such is life :D.

    And, let me be clear, even though I have a question, I am Very Happy to have this medal and have no problems with the purchase.

    I do have a bit of a question though. My photos vs. the auction house are very different. Clearly the same piece as all the other marks are there but the appearances of all of them are so very different given the photo skills.

    My question is looking at some of the surface issues (close up near the hippocamp's jawline is the most obvious)--I didn't see it on the auction photos, and I wonder if that is something that can develop (ie if they used old photos), vs. just not well elucidated in their shots.

    detail compare.jpg
    My shot is on the left and the right is a crop from the auction photo.

    And most importantly, is this an ongoing process that needs to be addressed? In other words conserved? I don't usually fuss so much over medals, but if it's 'fresh' I really want to arrest the process.

    @yarm @Insider (I think I'm tagging folks who know this stuff)
     
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  3. Seattlite86

    Seattlite86 Outspoken Member

    @messydesk you might have some insight on this.
     
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  4. Stork

    Stork I deliver Supporter

    OF course! I'm leaving off too many good people!
     
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  5. Pickin and Grinin

    Pickin and Grinin Well-Known Member

    First that is a neat medal. I am imagining that it is Bronze.
    I am not sure what has grown on the coin but it would try and remove it before it gets to bad. Is it green in color?
    At first glance it looks to be some built up gunk.

    I will also wait for the opinions of folks that have restored these coins, but I would try a quick soak in acetone and see if it. A) Turns color or B) Just comes off.

    It seems like a quick turn from auction house to you.
    Hopefully it is an easy fix.
     
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  6. Stork

    Stork I deliver Supporter

    Not green, just a darker brown. I haven't tried a thing and honestly I'd be more inclined to send it to NCS...but I don't want it in a slab and they auto-slab things now. At least last time I checked.
     
  7. thomas mozzillo

    thomas mozzillo Well-Known Member

    Very nice medal. The auction house sure did their best to minimize the gunk around the head. If it were mine, I'd try @Pickin and Grinin's method first. Maybe you should also start a thread on the Ancient coins forum. Those folks seem to have a lot of experience with conservation methods. If you do send it in to NGC's conservation service (or PCGS), you can always crack it out of the holder or ask them not to put it in a holder.
     
  8. Jwt708

    Jwt708 Well-Known Member

    Do you have an auction image of the entire medal?
     
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  9. messydesk

    messydesk Well-Known Member

    Weird. Is the bit on the coin some sort of raised gunk or corrosion, or is it discoloring that's smooth and flush with the coin's surface?

    Your picture and the auction one are lit slightly differently, so it might be possible that the light could hide discoloration in the surface. Your picture is also sharper. I don't think lighting would hide raised gunk, though. Do you have a link to the original auction? It's possible that the image was retouched using a clone stamp, but I can't see a match for what would have been cloned in the image. It might show up on the picture of the full medal. It does seem odd that someone would touch up only this area, as I can't imagine it affected the price by much.
     
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  10. Stork

    Stork I deliver Supporter

    Well, that was interesting. Looking at it through my camera lens it looked totally raised.

    I just took another look using a loupe and different light and the awful raised look in my photo is barely noticeable. And it's darker/mostly flat, just a bit of irregularity to the surface. It almost looks oily-ish like some leftover surface oil/treatment which may have reflected my lights very differently.

    What looks like a lot of surface debris around the jaw...is flat and darker. There is SOME increased texture, but not nearly like my shot.

    I had tried a modified light ring set up...with LEDs that required some color correction. I'm guessing that must have really done that.

    Comparing in hand to the auction photo, the auction is way more accurate. Interesting and too bad I hadn't looked at it with the loupe first! And crazy how bad my shots made it. I'll be re-doing them for sure.

    In any case, I had no doubt the auction pictures were honest...just different. And, confirmed better now that I looked closely without a camera lens.

    It was Stacks after all! I think the site was down earlier but I can link it now. Please no judging at how much I paid (my typo was pain...not too far off). I REALLY wanted this one. https://auctions.stacksbowers.com/l...le-bronze-medal-1759-george-ii-extremely-fine
     
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  11. Jwt708

    Jwt708 Well-Known Member

    If it makes you feel better, I think their estimate was very low and unrealistic. If you're happy with the price, that's what matters! Much more than that, I can't comment on the price, these are not my area. But it is a very nice medal!
     
  12. messydesk

    messydesk Well-Known Member

    Good to hear that it was an unintentional lighting side-effect, and that the coin looks better than what you photographed at first.
     
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  13. Pickin and Grinin

    Pickin and Grinin Well-Known Member

    It adds to the eye appear the little bit of dust and evident circulation.
    It looks like an honest piece though.

    I would leave it alone unless the areas grew. I don't always recommend it but,
    I have had to oil some coins in my collection. It can arrest some forms of corrosion that is otherwise just a futile attempt.
     
  14. GDJMSP

    GDJMSP Numismatist Moderator

    The only reason oil seemingly stops or slows down corrosion is because oil provides a moisture and air barrier - and without moisture and air, additional corrosion stops. But whatever has already been done, is done forever.

    Oils have an additional problem of their own, their effectiveness is temporary. And once the oil reaches a certain age, and that age varies with each type, it can have its own downsides, and even be harmful at times. And once that begins then the oil has to be removed.

    And sometimes, oil that has been in place for a long time gets a look to it that is very similar to what we are seeing on this particular coin. Ya see, oil on a coin, even when spread ever so thinly, is like a sticky agent. Dirt and contaminants in the air stick to it, they become adhered and accumulate, particularly in the protected areas like right at the edge of the devices because the oil is thicker there - there's more of it there. And those contaminants, well, they can create their own corrosion.

    A better solution than oil is simpler, and has none of the downsides of oil, but it requires a bit more effort - proper storage. Proper storage limits air and moisture to the point that their effects are negligible, or at least slowed so down so much that it cannot be noticed.

    So, @Stork , what to do about the coin ? Can't be sure of course, but what I do know is this. Pictures are always different, some show things some don't things. Even when the lighting is exactly the same, camera settings are exactly the same, if there is even the tiniest change in angles - one pic will look different than the others. So yeah, pics can hide things, but they can't show you something that simply isn't there. If a certain pic shows you something, well then it's there.

    Anyway, looking at your pics, the full size pics not the closeups, it looks to me like there is an accumulation of "something" in the more protected areas. The same kind of something that you can see in your closeups. Looking at the auction pics, I see the same kind of thing, just not as much of it as I can see in yours. That indicates to me that "something" is there. Could it be an accumulation of oil and contaminants ? Yup, sure could, but it could just as easily be almost anything else. But, if it was just corrosion, I would expect some greenish cast to it - and I don't see any of that, not even a tiny bit. And I'll admit I'm guessing here, but it's educated guess - and oil and gunk buildup would be my guess.

    If it were me, I'd give it a good soak in xylene. And every now n then picking it up by the edges and swishing it around, vigorously if ya can. Then put it more clean xylene and let it soak some more. Repeat that process 3 times with a final rinse in distilled water. Then stand the medal on edge and let it air dry.

    And yeah, I already know all the arguments about my suggested last step - heard 'em all a thousand times. But I stick to my advice. That's what ya asked for advice, and now you have mine. Up to you to listen or not.
     
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  15. Jwt708

    Jwt708 Well-Known Member

    Would xylene drastically alter the medal? I've never used it, only acetone.
     
  16. GDJMSP

    GDJMSP Numismatist Moderator

    Nope, xylene won't have any effect on the coin itself at all. It's exactly like acetone in that regard. But, it will remove quite few things that acetone will not. And, it doesn't have the effect of sometimes turning copper or bronze or brass weird colors that acetone does.
     
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  17. Stork

    Stork I deliver Supporter

    Looking at it closely some more I do agree there is a something, and it looks like what you say..oil and funk on it. My photos completely exaggerate it.

    I’ve got an unopened container of Xylene maybe it’s time to try it out. I was hesitating a bit on the acetone. Only concern is if there is a color change from being protected by the oil-gunk layer.

    Sounds like my weekend project including new photos is set. Unless I just say to heck with it and let NCS have a crack at it. It was’t my MOST expensive medal, but far from my cheapest. And one of the more elusive.
     
  18. Jwt708

    Jwt708 Well-Known Member

    I had used acetone on a few tokens - aluminum and brass - to remove PVC residue and the brass changed color slightly. Good to know about the xylene, I have a few ancients and tokens requiring PVC residue removal.
     
  19. Stork

    Stork I deliver Supporter

    Well, I ended up taking a few shots over as I got a couple coins in the mail. Used my more standard 4x lights with diffusers over them (daylight LED things). I think the oddball lighting in the first attempt had me fiddling too much with the exposure corrections and I overdid it with the 'shadows'. This one I barely did anything to and it definitely looks like some schmutz (the technical terminology).

    combo e3e3e3.jpg IMG_0161 copy 2.jpg
     
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  20. The Eidolon

    The Eidolon Active Member

    Xylene is a nonpolar organic solvent and acetone is a highly polar organic solvent. They are both very good solvents, but in general, like dissolves like. Polar solvents more easily dissolve polar contaminants, like most salts and oxides. Neither should be very reactive with copper metal itself, but I would guess acetone would be more likely to react with some corrosion products or contaminants. Xylene is pretty unreactive. (Both are flammable.) My guess is you are not looking for the fastest or most powerful solvent, but one which can do the job with the least interaction with the rest of the coin and its natural oxide coating.

    Disclosure: I used to be a chemist, but only used xylene etc. for surface science research, and haven't tried using it to clean coins.
     
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  21. Jwt708

    Jwt708 Well-Known Member

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