Hi everybody! I have recently bought via ebay few Australian coins. All are not valuable ones and still the seller sent me 2nd grade ones with annoying faults. You can see those faults on the attaced jpeg -from left to right: 1. green corosion on a copper coin 2. A tape which was attached to the coin pealed off some of the patina 3. Some green lines near the Roo's head and 4. black dirt over the inscription of the silver. Again, I know these coins are not valuable but presenting them in my collection seems to me to be out of the question on the current state. Is there any way to clean the green crosion marks, the patina and the dirt. I am not bothered at all with loss of value but still wouldn't want to destroy there overall apearance. Any help would be much apreciated. Thanks, Avi
I really think we need a separate forum for cleaning coins. That subject is repeated just to frequently. However, for you cleaning problem, since you don't care about the coins that much, just go to Walmart. Go to the jewlry department and buy a jar of jewlry cleaner. Tarn-X will also work and some Walmarts will sell you Tarn-X as the jewlry cleaner. Put the coins in there for several hours, rince with distilled water, blot dry with a napkin. There are tons of other methods also. Put the coins in a pan, add water, bleach, lemon juice and boil. Also, ammonia will help but don't put that in the same pan with bleach. A fast dip in battery acid works but not realy good for your fingers. My favorite is plain old baking soda and water solution and gently rub. The most important thing is to always rinse your finished product in distilled water. Good luck and let us know what you ended up doing.
Hi Guys, Carl and PyrotekNX - thank you for your replies. Here are some results. Since I live in Israel Walmart was not an option but nevertheless I did try some cruel techniques. So from left to right: Coin 1: Wad dipped in soap and warm water and then in vinegar. The problem I found is that the green corrosion is more resistant to the treatment so by the time it was gone the nice patina was also gone. What I did notice is that after several minutes the coin (apart from the green corrosion) looked really nice i.e. it looked as new and did not loose its lustre. Since I kept it a while longer in the vinegar it became the ugliest cleaned coin you can imagine. Coin 2: Got the same treatment as Coin 1. What I thought was a tape is something totally different. Some kind of nasty stuff was put on that coin some when along its history. Cleaning it revealed the fatal wounds it already had. Coin 3: Got the same treatment as Coins 1 and 2. What seemed to be green lines of corrosion are actually corrosion inside some nasty scratches. Again the coin is now suffering from both scratches and also from my cruel treatment. Coin 4 (The silver): Was dipped in a dish washer soap and warm water. The results are very good. Some of the dirt is gone (it looks better than the scan) and the coin did not get the polished look cleaned coins usually get. This has to do with Carl's advice about how to dry it. So - to conclude. I saved one patient (the silver), killed another (coin 1) and found out, after the operation ended, that nothing could be done for the other two (coins 2 and 3). More or less the statistics you would find on any E.R. on hospitals (Just joking). Would love to hear what you guys think. Just to remind you - I am just a beginner and did not mind fooling around on some cheap stuff. Avi
Chemistry wise, once you have verdigris on copper coins, there is nothing you can do, except to slow it's rate of damage, or dip it into olive oil and let olive oil slowly eat away the corrosion. But remember olive oil itself is a weak acid. Of course that explains why vinegar helps in the cleaning because it's a stronger acid than olive oil. Time itself is a factor - sometimes if you leave it in the solution for too long, you might as well let the coin dissolve in hydrochloride acid...
For just plain dirt, soak it in distilled water for an hour or so and then freeze it. Repeat if necessary. You might be surprised by the results.
ghseries: Thanks for the information. I will try the olive oil soon and post "before" and "after" pictures to show the results. GDJMSP: Thanks for the information. I am not sure I am going to order yet but sure will in the future. SuperDave: I tried it with an extremely BLACK DIRT silver and it worked (to an extent). I have not scanned the "before" and "after" but will do with the next one. Thank you guys for the information - it's very kind of you, Avi
