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 Replies: 20 / Views: 4,637 |
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New Member
 United Kingdom
37 Posts |
Pacificoin,
When you eat salad, you can even squize juice a bit from tomato in a cup and put coin there. But like it been said, tomatos are acidic and need to be careful.
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Pillar of the Community
 United States
7941 Posts |
To my eye, you improved that coin quite bit (as long as the scratches were already there). It sounds like you have experimented enough to know what you are doing.
Tomato juice is a fairly weak acid. It is about 100 times weaker than lemon juice or most vinegars. Probably this fact, plus the need for the acid (juice) to diffuse through the tomato pulp, makes it a more slow, gentle form of "cleaning with an acid" than other approaches.
I see this coin is made of Ni-Brass alloy. I would guess the results on other compositions could be very different.
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Pillar of the Community
 United States
6559 Posts |
Quote:
To my eye, you improved that coin quite bit  And someone had to do something to save that coin |
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New Member
United Kingdom
37 Posts |
tdziema
Yes, I dug it in the woods (Lithuania) and scratches were already there. In some places soil can be very acid. Not to mention how bad it is in UK. But I am talking only about those coins that are found in the ground and in poor condition. Not to make illusion for people that I buy and ruin coins with toothbrushes or sanding paper :D No, no, I don't do that. Only experiment with coins that have no value and need attention.
You are absolutely right. Diffusing tomato juice would really make things so much better. For me it ideally work to remove green oksids from silver coins and it doesn't make metal shine or damage patina. All detectorists came across with this problem.
Regarding metal composition, with copper coins you need to be careful. It can leave gingerish color on the coin and it not always can work ideally.
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Pillar of the Community
Canada
1081 Posts |
Whether you're cleaning with a tomato or toning with a boiled egg - it's a chemical treatment of a coin. Once it's done, it's not un-doable. I take the point that this coin was in decidedly weird shape. So there may be exceptions towards the bottom of the heap. But they are exceptions....
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New Member
United Kingdom
37 Posts |
Silver101,
All people are with different taste ;)
Better than tooling, smoothing coins and selling to people without letting them know :)
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Pillar of the Community
United States
7941 Posts |
To me, you started with a coin that is really not presentable to a numismatist, and your result was still some uneven patination, but a coin that is now collectable.
It is only different in degree from the result obtained when an ancient is professionally "conserved." Although I agree with many earlier comments that one must be very careful with any approach like this.
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Bedrock of the Community
United States
20753 Posts |
Chemically every Tomato is different. Therefore this is rather dumb since one Tomato may do little and the next one could melt the coin. Not really but could do a real number on it. And don't forget nowadays there are numerous different Tomatoes. So should we be using Red ones? Yellow ones? Striped ones? etc., etc., etc,? Round ones, pear shaped ones, large or small ones?
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Pillar of the Community
United States
4085 Posts |
I can only recommend cleaning coins with homegrown tomatoes.
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Rest in Peace
United States
18456 Posts |
The ones that I recommend are the Organic Italian Plum Tomatoes . Guaranteed to strip the Zinc right off a U.S. steel cent .  |
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Moderator
Australia
16830 Posts |
Metal detector finds are an example of an exception to the general rule "never clean coins". Keep them uncleaned and you might have an "interesting historical artifact", but you don't really have a "coin" - especially if it's unidentifiable as to country, denomination and date. Acids (including tomato juice) are towards the "strong" end of cleaning agents. Acetone is towards the "weak" end, as it only removes organic "goo" and leaves the metal and any metal corrosion by-products alone. This coin was covered in green corrosion by-products; acetone would have done nothing. Quote:
Actually, I rather prefer amonia + soap water and boil it for few min. Ammonia and soap-water are also "weak"; I do not know how they work when mixed together and boiled. I do know concentrated ammonia alone, on copper/bronze coins, tends to leave an ugly, bright orange discolouration once the corrosion is removed. This Romania 10 lei coin is made of "nickel-brass", and so would probably also have enough copper in it to turn orange too. I think you made the right choice in going straight to mild acid. Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis
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Bedrock of the Community
Australia
21788 Posts |
, Sap has said it right for this coin. |
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Pillar of the Community
United States
7941 Posts |
Ammonia forms colored complexes with transition (i.e. coinage) metals. This is known in the chemistry world,and might also apply in this instance.
Common acids do not.
Edited by tdziemia
03/29/2020 8:21 pm
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Moderator
United States
188561 Posts |
Quote:
And someone had to do something to save that coin It is better off now. |
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Bedrock of the Community
United States
17884 Posts |
I think most of the "cleaning" of the OP coin was accomplished by the toothbrush.
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Replies: 20 / Views: 4,637 |
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First Page
Posted 03/28/2020 3:20 pm
