I have some lincoln cents from the early 1900's that would grade VF-XF however they have a considerable amount of blue/blue green corrosion on them. Should, and if so how to remove it is the question.
interesting, i have never heard of or thought of hydrogen peroxide , i'll try it and if it works, add it to my 'arsenal of knowledge' and include it in my ' destroy the roll ' theory of beginner education talks...........
It's common Jack, many use it to clean dug coins. Heating accelerates the process. Sure doesn't mean I would recommend it though.
I haven't tried Verdigone but shot glasses filled with peroxide then microwaved for a few seconds works great. Peroxide is about a buck a quart or there about. Cheap, gets rid of the crap and leaves the copper.
Yes, but it also leaves the coin in such a state that an experienced eye can easily see that it has been chemically cleaned. Verdigone does not.
What is Verdigone? where can I get it? it seems a side by side test with examination under magnifcation is in order.
Proprietory. Maybe you can convince badthad to tell you, but I doubt it. Read http://www.cointalk.com/forum/t51146/ Read http://www.cointalk.com/forum/t48402-2/
Yes, but it also leaves the coin in such a state that an experienced eye can easily see that it has been chemically cleaned. Verdigone does not. I just sold some Lincoln cents to my local coin shop that I pulled out of circulation (after searching boxes and boxes) that were subjected to Peroxide soaking, water rinse and then a half a drop or so of mineral oil between my fingertips. Looked great and I got no mention of cleaning from this gent, and he looked at all of them pretty hard. Verdigone may indeed work better, as I would have to defer to your experience with it, but, Peroxide works great too (at least for circulated coins).
I have tried peroxide and it worked pretty nice actually. If a coin has blue/green corrosion then getting it off it priority. The coin will look better no matter what if you get it off. I agree with Tom on this one. I have never heated peroxide and will try. I have a few wheats and IHC with lots of corrosion and I will try. Thanks for the idea Tom.
With respect Tom - more than quite a few coin dealers really don't know squat about coins. Understood Sir. I appreciate the input and take it graciously knowing that you have the experience to back you up. I do wish I could convince you to be a little more generally accepting of (at least) this particular method, but I know where you're coming from. Good day.
I think we need a "Jim style" experiment with heated peroxide. I have a VF 1923 S copper that was sitting in Verdigone for a long time with green corrosion/verdigris. Sat for several weeks with 2-3 changes in of the semidiluted Verdigone (about 30% distilled water with 70% Verdigone). Size of corrosion slowly decreased but is decreasing faster with peroxide. Maybe I will do some before/after experiments on other coins with photos. I would debate that others could tell such was done to a given coin. Coins with corrosion or verdigris are ugly in my opinion and I want that stuff off. My eye only goes to the damage.
Boss, watch carefully for darkening a while after the peroxide treatment. Since it is H2O2 and breaks down into water and oxygen, It seems chemically possible that copper without a natural patina could combine with the active oxygen to make CuO which appears often as 'carbon spots' after a period of time. By the way, you can get 30% H2O2 from chem supply, but it is real bad stuff unless you are building a rocket. Yea! an experiment!!!:eating: I am still trying to understand BIOX enough to start one on it. Can't get the repeatability level of Verdigone. May be a while for that. Jim
I just do not understand why someone wants to change the apperance of a coin or buy one that they suspect has been cleaned ?
