Okay, I have all these cleaning supplies on the market. I clean ancients all the time and with pretty good results but to be honest, there is a world of difference between cleaning a copper coin that has been buried for a thousand plus years and cleaning a newer coin that is in great shape but simply has some tenacious surface build up. You want to deal with that problem but otherwise you want to keep it exactly how you got it. The recent thread about the coin transformed from a mess to a nice looking coin has prompted me to think I have a lot to learn about cleaning more modern coins with serious problems with a bare minimum of surface damage (and lets face it, often times its clean it or it corrodes). Are these super secret cleaning techniques or can someone here tell us how a coin like that would be treated and what with. I have found the people in the ancients world to be pretty open with knowledge like this, is this the same in this case? I am a do it yourself type person and I want to learn more about how one would help a coin in this condition as I have a few like it myself, when you buy ancients and very old coins they are often very nice but have some problem like black oppressive tone (corrosion) or some tough surface crud that is truly distracting from the beauty of an otherwise outstanding coin, a coin in great shape but for one little thing. Much of it I can deal with, others not so. Now this is my hobby, the less people I have to pay for anything the better. As its my hobby, I want to learn everything I can. I have found that with cleaning a coin or any manual task its just a matter of knowing what to use, when, and how. This is a coin forum for learning, how about we hold a little experiment, a learning process for us all. Now if these are closely guarded secrets to keep people paying for it to be done, no problem, I will simply have to do more research myself, but if someone here is actually 'in the know' about cleaning (conservation) and can walk us through one example, that would be great. I am willing to acquire whatever I might not have and need for this project (to a point of course) I have a silver dollar that has some crud on it that acetone does not take off, I also tried a dip but it still did not come off. Admittedly I used the dip just very briefly, same with the MS70...I used that as directed and this is still on the coin and remains largely unchanged. So to be honest aside from scrubbing it harshly, I am a bit out of ideas. This coin is already only worth bullion as it seems someone else has tried to scrape whatever it is off. I guess you can make it at least look better...or look worse than now. You wont make it worth much less I would think...and I'm not selling it and it will be a well documented cleaned coin. Here is the coins problem areas: Now I thought they might be some type of glue or adhesive that hardened on the coin but I would think acetone would deal with that as it has in the past. I just dont know with this coin. How about someone in the know walk me through cleaning this off?
I don't know, it kinda looks like salt stains which should come off in warm water. Maybe lemon juice and salt or baking soda and lemon juice since the NDC techniques failed. You're in an area I've never had to venture since the free-wheeling brillo pad, brown penny days of the late 60s. Take Care Ben
I'd try Ben's soaking idea first. I have also tried soaking silver coins in WD-40 for several days to remove surface dirt, and also lightly brushing away some surface junk with a new soft-bristled tooth brush. I know none of this is actually good for a coin, but neither is leaving some potentially corrosive stuff on the surface. I've been satisfied with the results but have only experimented on circulated or already damaged coins.
When you used the dip, did you rinse with distilled water or tap water ? Tap water will leave mineral deposits that look very much like that.
I used distilled. These were already there before the dip. The first thing I tried was just a long soak in distilled water, I then used water with a touch of lemon to soak for a while. I soaked for a very long time before I attemted to use a bit of acetone. The coin IS already damaged from a previous owners scrub but I think that just means a manual scrub didnt do anything (or much) to remove it. Its interesting, whatever it is... its tough. If I had even a clue as to what it is it would help I guess.
Drusus if you have tried a commercial dip on that coin - which one by the way ? - it may well be that what is there is the remains of having something previously removed, possibly PVC that ate into the surface of the coin. If this is the case, nothing is ever going to remove it. I say this because most commercial dips will remove just about anything - including some of the metal.
I was afraid of that. I didnt want to dip it again because I know it could eat the metal. The dip I used was EZest. This made no noticable change...so I tried MS-70 as my last effort...same...That was the end of my rope. I showed this to you and you said you thought it was something on the coin that might be able to be cleaned off so I tried this I fear it might be something that ate into he metal, like you say, and there is no changing it...though to look at it it sure does seem to be on top of the surface...oh well...
