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 Replies: 36 / Views: 13,498 |
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Pillar of the Community
United States
1691 Posts |
I have been following with interest the topic on indian head nickel (buffalo)using Nic-a Date or similar acid based products to restore the date. Is there any way to restore the date on a silver coin such as the Standing Liberty quarter (which suffers the same design flaw)?    |
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Moderator
 United States
16679 Posts |
I am not sure but let me tell you this. DO NOT use Nic-a-date! It will put a permanent black stain on your SLQ or any silver
swcoin.ecrater.com
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Pillar of the Community
United States
812 Posts |
To the best of my knowledge, there is no way to restore a date on a silver or copper coin, just on nickel.
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Pillar of the Community
United States
1424 Posts |
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Is there any way to restore the date on a silver coin such as the standing liberty quarter There sure is....with this baby you can make it any date you want!   Edited by bmanofnbc
11/30/2008 8:48 pm
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Bedrock of the Community
United States
14454 Posts |
someone that knows metallurgy may know some type of acid that is strong enough to eat away at silver and not to strong that it eats away all the silver just the weaker parts around the date where the metal is weaker
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Pillar of the Community
United States
5611 Posts |
BMANOFNBC, I BELIEVE YOU HAVE THE RIGHT APPROACH, AND A GREAT SENSE OF HUMOR!!
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Pillar of the Community
United States
1291 Posts |
Hello to all! I believe that there was a product on the market years ago that worked on silver coins. I've never been able to locate any. Some old timers might remember the name. Someone once told me that nitric acid might work, so I suspended the lower third of a SLQ in some and the next morning I found that I had a 14 cent piece. Bottom third was GONE!
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Bedrock of the Community
United States
17884 Posts |
Most any acid will bring out the date since the principle is still the same. The problem is the black stain. The stain come from a property of silver. Most silver compounds turn black when exposed to light. This is the reason why film, especially B&W film photography works. Since light is the problem, I would probably try a mild acid such as vinegar on a completely opaque container. After soaking in the acid the acid would need to be poured off and then the coin THROUGHLY rinsed with water to remove any trace of the acid and the reaction components. Possibly a fixitive agent might need to be used as well. Unfortunately I do not know what they use as a fixitive in film development.) And all of this pouring off and rinsing needs to be done in the dark. If the date hasn't appeared, back into the opaque soaking container and start over.
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Moderator
Australia
16826 Posts |
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Most any acid will bring out the date since the principle is still the same. Silver is less chemically reactive than copper or nickel, so you have to be slightly more selective in choosing an acid that works. For example, hydrochloric acid, the main constitutent in "nic-a-date", is terrible for silver because silver chloride is insoluble in water. Nitric acid is probably the best, but make it really, really, dilute or only keep the acid in contact with the coin for a very brief period, or you will get that magical disappearing coin trick that weerdsteev observed.  Don't the folks that make nic-a-date also make a proprietary solution for silver, too? 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
United States
14454 Posts |
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next morning I found that I had a 14 cent piece I about spit soda all over my monitor when I read that |
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Bedrock of the Community
United States
12437 Posts |
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For example, hydrochloric acid, the main constituent in "nic-a-date" the active ingredient in Nic-A-Date is ferric chloride, not HCl Quote:
Possibly a fixative agent might need to be used as well. Unfortunately I do not know what they use as a fixative in film development.) Hypo, aka sodium thiosulfate is a common fixative As far as a silver etchant goes- you can use ferric nitrate, a solution of iodine and potassium iodide, or a solution of ammonium hydroxide, hydrogen peroxide, and methanol. I have not tried any of these methods and the constituents are not readily available in the proper concentrations. The iodine is a crystal form not your common topical antiseptic. Ferric nitrate is a bit toxic, and hydrogen peroxide is the 30% variety that will take your skin off not the 3% used as an antiseptic. You can also purchase commercial preparations used in the jewelery and electronic industries(just an example, I have never used that product). Edited by biokemist6
12/01/2008 11:26 am
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Pillar of the Community
 United States
1691 Posts |
Thanks to all for their insightful comments...especially BManOfNBC
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Pillar of the Community
United States
1291 Posts |
Bryan - Sorry about your near-soda episode! The other thing I wanted to mention is that it was giving off some kind of gas that almost knocked me out. Maybe biokemist6 can comment on that? I guess that's why they don't put 15% nitric acid solution in children's chemistry sets.
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Pillar of the Community
United States
1424 Posts |
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Thanks to all for their insightful comments...especially BManOfNBC Glad I could help!  Edited by bmanofnbc
12/01/2008 9:40 pm
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Bedrock of the Community
United States
17884 Posts |
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Nitric acid is probably the best, but make it really, really, dilute or only keep the acid in contact with the coin for a very brief period, or you will get that magical disappearing coin trick that weerdsteev observed. Another problem with nitic acid is that the reaction product, silver nitrate, is VERY reactive to light and the black stain it leaves doesn't want to come off at all. You would have to be really careful to remove all traces before you exposed the coin to the light. |
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Pillar of the Community
United States
2602 Posts |
Biochemist: do you know the ratios of ammonium hydroxide:peroxide:methanol? I might be able to try it and then report back here on whether it works. I have access to all three chemicals. Ammonium hydroxide is about the most aweful smelling chemical, so I wouldn't recommend this to anyone.
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Replies: 36 / Views: 13,498 |
Posted 11/30/2008 8:37 pm
