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 Replies: 10 / Views: 1,427 |
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New Member
United Kingdom
16 Posts |
I have been cleaning my ancient greek and roman coins with distilled water with little success. Today I found that one of the coin that I had left in a mug of distilled water left a gold stain behind. I scrubbed at it but it did not come off.
Does anyone know what this stain is and if it is safe for me to continue using distilled water to clean my coins.
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Pillar of the Community
United Kingdom
3626 Posts |
DW should not damage the coins. What was the container made out of? Almost sounds like rust.
Can you post pics?
Edited by pishpash
10/12/2013 3:12 pm
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Moderator
 United States
23731 Posts |
 to the community There must have been some type of dirt or sand on the coin that the DW loosened and left a deposit on you mug |
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Pillar of the Community
United Kingdom
4208 Posts |
If distilled water isn't working, move on to olive oil. The gold colour could be any manner of compound...probably based in copper. Id play it safe and not use the mug until you've removed the stain (leave some white vinegar in there and it should come right off). That being said, it usually takes a lot of something to harm the average person.
Also...you might be using deionised water, which isn't distilled. This could have some chemicals floating around to react with the coin (it shouldnt really). If it is dionised and the brand is causing this, id recommend buying from somewhere else (or distilling the water yourself).
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Valued Member
294 Posts |
Hi guys, I just bought some methylated spirits 95% pure, no idea what the other 5% is. I was intending to remove any possible PVC leakage on some copper coins that have been sent to me via post in 2x2's with PVC windows and one silver coin that's had a price tag right on the centre. Any past observations of undesirable reactions? I can't remember now but I'm pretty sure somebody's had problems with methylated spirits and cleaning. Thanks
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Pillar of the Community
United Kingdom
3626 Posts |
I would rather used acetone than meths. The others may have other advice.
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Pillar of the Community
United Kingdom
4208 Posts |
Methylated spirits will probably be able to photocatalyse with Copper to Acetic Acid and other Carboxylic acids. The other 5% will probably be colouring and other compounds. Id recommend against it - try Acetone, its easier to get pure. For extra cleaning power, whack it in direct sunlight but dont leave stuff in there too long. in darkness, you can leave it for as long as you like.
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Valued Member
294 Posts |
I'm sorry but I thought it was acetone that would photocatalyse and yield acetate salts? either way they unfortunately don't sell pure acetone here, only nail polish remover which likely has impurities. But would silver also react with methylated spirits? perhaps I should have bought denatured alcohol instead?
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Pillar of the Community
United States
5155 Posts |
The problem with using methylated spirtit is that distilled hydrocarbons act as cleaers. If you decide you want to soak your coin in it you will likely being to wash away any of organic compounds that my constitute a patina. The same does for denatured ethanol. Without acetone it seems you might actually be quite limited. Most other "chemicals" do not work nearly as well.
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Valued Member
294 Posts |
that's a bummer... guess I can't leave the bottle wasting away there. I shall try it out on my very cheap coins and see what becomes of them just to learn. thanks guys.
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Valued Member
384 Posts |
Just spotted this whilst looking for cleaning threads .......
One piece of invaluable advice I CAN give to ancient coin cleaners is to ensure that if you are going to clean an ancient crusty (and this may seem obvious, so I apologise in advance).... ALWAYS do DW first then olive oil afterwards and never the other way round. this may sound so obvious , but I have seen people do it in other forums and it will not work. water will not penetrate an oil soaked coin. Also, always ensure that after DW the coin or slug is dried....I mean bone dry (oven at 100 degrees for several hours as a minimum) BEFORE putting in olive oil. That way the oil will penetrate fast and do its job. In fact I would put the coin in the oil straight from the oven as it helps raise the oils viscosity.
water and oil do not mix, so do not expect the oil or water to penetrate the coin/grime with the other still present (and its nearly impossible to get rid of oil from the coin), whereas water will evaporate.
Just a few simple pieces of advice and as I said I do apologise to those of you to whom this seems obvious already!!
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Replies: 10 / Views: 1,427 |
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Posted 10/12/2013 6:09 pm
