Waxy substance on 1801 Ruble - can be removed safely?

[savok]

I have a Paul I 1801 ruble that came through my wife's family, kept for 100+ years, so I have no doubts as to authenticity.

 

There appears to be a coating of something like wax (from candles?) on it that has delaminated from certain areas (look especially at the secdond line text "NE NAMb"). Note how the flat field areas of the coin are dark and the raised areas are "normal" looking, something that this substance appears to have caused. I am wondering if it would damage the coin to dip it in boiling water in the attempt to melt this substance off.

 

Take a look:

 

http://i206.photobucket.com/albums/bb177/b...ble_Obverse.jpg

http://i206.photobucket.com/albums/bb177/b...ble_Reverse.jpg

 

opinions?

[savok]

Nobody has an opinion?

[amac44]

try acetone

[LostDutchman]

i agree... soak it for a couple of days... it should help

[savok]

try acetone

 

acetone (i.e. nail polish remover) won't do anything to damage the metal?

[squirrel]

hot water would be ok, i think, for the coin. the only thing is, once the wax melts off, the silver that was protected by the wax may have a lighter tone or patina than the unprotected areas.

 

I picked up a similar coin, 1798 ruble, well circulated, uncleaned, but previous owner had brushed polyurethane or varnish on both sides (was only $30)

I held my breath and applied methyl chloride paint stripper(the can said safe for metals ) It removed the clearcoat, and MIRACULOUSLY left the nice dark patina intact.

Good Luck!

[LostDutchman]

I have never had a problem with acetone doing anything to the coins originality. I do like to hot water idea tho too... if it is wax that might do it

[bobh]

try acetone

i agree... soak it for a couple of days... it should help

If you use acetone, don't use nail-polish remover (which includes acetone as the active ingredient, but also a lot of other stuff...) Use the pure acetone which you can buy either at a pharmacy, at a paint shop, or at Home Depot in the USA or some other type of home-improvement or hardware store. I live in Europe, and since I never need more than tiny quantities of acetone at a time, I always get mine at the local apothecary in bottles of approx. 200 ml or less ... much cheaper that way, and less headaches for storage of the stuff.

 

It is HIGHLY FLAMMABLE, so please take appropriate precautions!

 

Acetone is mostly OK for silver and gold coins. However, please don't forget that most of these also have approx. 10% copper included in the alloy, and acetone has been shown to react with copper in the presence of water and light. Acetone does not react with pure silver or pure gold, though.

 

I would soak the coin for only a few minutes and see if there is already a marked improvement. First, be sure it is dry, though. If no improvement is noticeable, and you think you have to soak it overnight or longer, please do it in complete darkness ... otherwise, there might be an adverse reaction with the copper in the alloy.

 

And please don't forget that acetone might be highly reactive with whatever container you use to soak the coin in. For example, if you use a little glass jar with a tight-fitting lid, there is usually a rubbery substance lining the lid which seals with the glass. This WILL BE dissolved by the acetone vapors after a couple of hours or less and possibly deposited onto the coin! That is why I seldom soak a coin in acetone for more than a few minutes ... it is usually enough with most organic materials which you might be trying to remove (wax, old globs of jelly, PVC residue, etc.)

[Drusus]

before you use acetone, I would try very hot distilled water....

[savok]

before you use acetone, I would try very hot distilled water....

 

I tried boiling distilled water, lowering the coin into it in a perforated ladle. This did not work. I tried my wife's nail polish remover, unfortunately it said on the bottle "non-acetone", so that's all I had to try with. I poured a sufficient quantity over the coin in a ceramic dessert bowl. Nothing changed.

 

The question now is: would REAL acetone make a difference? what would be worth trying next, that would not damage the coin?

[sigistenz]

and acetone has been shown to react with copper in the presence of water and light.

Hi Bob, I have never heard of negative effects of acetone with copper. I bathe some copper piatak from time to time in acetone in bright daylight to make sure that there is no grease on it. This in order to further treat it when stained or covered with verdigris. So far without seeing any side effects. What makes you think that there were any? Or are they still to come?

Thank you, Sigi

[bobh]

Hi Bob, I have never heard of negative effects of acetone with copper. I bathe some copper piatak from time to time in acetone in bright daylight to make sure that there is no grease on it. This in order to further treat it when stained or covered with verdigris. So far without seeing any side effects. What makes you think that there were any? Or are they still to come?

Thank you, Sigi

Here is one link:

Photochemical breakdown of acetone on copper

 

And another (PDF file, look on page 4):

Australian National Pollutant Inventory - Acetone Fact Sheet

 

Here is a quote from that document:

"Acetone can polymerise rapidly due to heating and under the influence of air, light and on contact

with a catalyst, strong oxidisers and metals such as copper and aluminium, with fire or explosion

hazard."

 

The effects probably aren't noticeable on older circulated copper coins such as the 5 kopek pieces. It is more noticeable on red uncirculated copper coins.

[sigistenz]

Here is one link:

Photochemical breakdown of acetone on copper

 

And another (PDF file, look on page 4):

Australian National Pollutant Inventory - Acetone Fact Sheet

 

Here is a quote from that document:

"Acetone can polymerise rapidly due to heating and under the influence of air, light and on contact

with a catalyst, strong oxidisers and metals such as copper and aluminium, with fire or explosion

hazard."

 

The effects probably aren't noticeable on older circulated copper coins such as the 5 kopek pieces. It is more noticeable on red uncirculated copper coins.

Thank you Bob! As you said my old copper piataks did not show any signs of change when soaking them for a few minutes. But it is good to know that there could be harm. I'll avoid acetone from now on, using PROPYL ALCOHOL instead for degreasing (not too expensive in pharmacies).

Thank you also for your information on the Geneva sale to come.

Best, Sigi

[savok]

I finally had the chance to get some acetone, and my coin has been soaking in it for five days now. No change at all. Whatever is coating this coin is apparently resistant to acetone.

 

What the heck could this stuff be? Any other ideas?

[squirrel]

I picked up a similar coin, 1798 ruble, well circulated, uncleaned, but previous owner had brushed polyurethane or varnish on both sides (was only $30)

I held my breath and applied methyl chloride paint stripper(the can said safe for metals ) It removed the clearcoat, and MIRACULOUSLY left the nice dark patina intact.

Good Luck!

 

shellac, varnish, polyurethane, clear paint etc...