I recently purchased an auction lot of albums from Norway. The majority of the albums were in fairly good shape, although they smelled a bit musty. However, there were several pages of soft vinyl holders filled with iron coins that are severely rusted and corroded. These are mostly WW II issues under the German occupation, but also some WW I issues. There is the possibility of finding overdates and varieties, as well as less-common dates among these 1, 2 and 5 ore coins. But in their condition it would be difficult in many cases to even determine the year. Does anyone have any suggestions? Or are they beyond all help? These should be fair warning about storing susceptible coins in vinyl and what must have been long-term dampness. Steve
No, because the rust has destroyed the design features on the coin. There is nothing to clean because the oxidation has left nothing. The CSS Virginia token made in 1906 from iron recovered from the wreckage of the Confederate ship have the same problem.
The vinyl is probably made with PVC. The damage is done. You might play with one of the really bad ones just for fun. Start with an acetone bath to remove any PVC. Next soak it in some type of oil for a while. Next an acetone bath to remove the oil and put the coin in a fresh holder. This won't help much but the coin may look a bit better.
There comes a point at which inexpensive coins with excessive damage cannot get any worse with conservative cleaning. If your coins are not valuable I think you can clean them. How? Well, that's a different question.
Yes you can conserve iron, but the coin has to be a good candidate for it. Excessive rust that has been untreated means there will be pitting on the surface. It can't be saved. What can be successfully treated for iron or mild steel are very minor rust spots.
Thank you for responding. How would you recommend doing this, as of the hundreds in the lot, some have very minimal spotting. Steve
Acetone first to treat the PVC, then VerdiCare to spot treat the rust, followed by more acetone, and then light mineral oil. It is very time consuming and so not really worth treating unless it is an especially valuable issue that is also a good candidate for conservation.
Acetone won't do much to remove oil. To remove oil you need to use xylene. But I agree with you 100%, the oil will need to be removed ! After that, proper storage, and taking extra precautions to minimize humidity, is the best bet to protect the coins.
sort your coins down by condition. Take the worst coins and divide into four or five guinea pig lots. follow the recommendations and go with the one that provides the best results. add this technique to previous suggestions. soak in wd-40 and allow to air dry. once dry rub gently with soft cotton rag from old tee shirt. soak down again and repeat process until dried coins do not lose rust when rubbed by soft cotton. I thought some of those coins were zinc. When cleaned zinc bleaches to a pale grey with almost no details. When I was metal detecting in germany nazi coins were washed then the zinc ones were painted with black magic markers to contrast the details so that we could read mint marks. good luck
Thank you, @harley bissell. I’m going to try several methods on small lots, including your WD-40 method. Apparently I have nothing to lose with the worst of them. I’ll keep a photographic record and post the results. Zinc was used in WW II for higher denominations. Steve
objects like this from wartime don't just have numismatic value. A battle dug corroded common coin will frequently fetch more than the same coin in MS-65. You can expect the information from a coin collectors' site to be accurate regarding the collector value. To them condition is everything. Sometimes I do very well buying their rejects. The carbon spotted ms rejects from a BU roll of 1944-d cents yielded me two 1944-d/s beauties bought at a coin club auction unidentified for minimum bid because all of the condition purists stopped looking when they saw the carbon spots. I would mark the worst of your coins as battle dug and see what they bring.
Some of those look like great candidates for electroplating. Acid dip and plate. Either way probably won't effect the value. Something like replating a us steel cent.
Using battle dug as a generic phrase. I don't name a battlefield unless I dug it there. All of my nazi coins were dug on the grounds of former nazi military bases and were lost during war time. I tried to avoid battlefields due to unexploded ordnance. Even on bases it was unsafe to dig large signals. Dug without qualifier would indicate found in a park or a yard. Dug US clad and coppers are obvious and I spot many in change. They aren't worth flips but make interesting sets in blue Whitman folders.
Verdicare was developed to remove verdigris (copper salts) from copper. I don't think it would do much with rust on iron. And considering how rare verdicare is nowadays I don't think I would waste it on corroded iron.
Yep I realize, but it also works quite well for removing light corrosion on iron, mild steel, zinc, and lead. Aside from copper, I use it to touch up special pieces - condition rarity wartime issues and the like for the above compositions.
