Licinius billon cleaning help

[fireproof]

Hello everyone, I've collected coins for years but am new to ancient coins. I recently bought seven uncleaned roman coins and two of them turned out to be silvered/billon! I'm saving the best one for last after I get a feel for cleaning but I wanted to get some opinions on this one. I believe it is a Licinius I RIC VII 27. The silver plating appears to have worn off where the greenish areas are but a fair abount of silver remains. The surface of the silver looks rough under magnification and there are still some areas of dirt after a quick DW bath followed by soap and water. I've heard some people using lemon juice but I think it might be too harsh for this situation. Would more distilled water and light brushing help or would that remove more silver?

[areich]

Silvered and billion are two different things. Your coin is a silvered (though I can't see any silvering from the picture) bronze, so lemon juice or any other acids are not a good idea. It would not be good for billon coins either.

[casata137ec]

I'd like to second aerich's opinion, in fact I'll go one step further, lemon juice would eat the underlying flan and the silver would flake away. Any more cleaning and you will ruin the coin. It is about as good as it is going to get.

Chris

[gavignano]

agree with Chris - done.

[SC]

Fireproof,

I am not so sure that it is done.

Look at a much larger thread on cleaning silvered coins

https://www.forumancientcoins.com/board/index.php?topic=42932.0

What you have remaining appears to be what I called "stained" silvering.  While most of the dirt is off it appears to still have a very thin but hard clay-like dirt layer on the silvering.

You might be able to clean this off by soaks in distilled water, with or without washing soda, and very gentle brushing with a soft toothbrush.  Just a plain soft toothbrush not a stiff, cut-down toothbrush and light circular motions.

You may be able to assist this by gentle scraping with a toothpick as well.  One of the thicker round toothpicks either with its point or cut like a chisel.

Finally you may be able to clean the silvering with a scalpel or exact blade.

HOWEVER, there are caveats.  These techniques work well when the silvering is intact. 

With yours some of the silvering is gone, especially from the high parts.  This could be just wear and the rest is stable, or it could be a sign that it is ready to flake off everywhere!

So be very careful and stop at the first sign of flaking.

Also I would not use the scalpel method until a) you are sure of yourself, and b) you have a stereo microscope to do it at 10x or 20x magnification.

Shawn

[fireproof]

Thanks for your input everyone. I was under the impression from the searches I'd done that billon was the same as silvered, but it's good to know there is a difference. I might try a bit more DW because I want to be able to see his eye, an important part of the portrait in my opinion, as there seems to be a little bit of dirt on top of it. For those of you who couldn't see the silvering, it's underneath that whitish-yellow stuff in the fields, but like I said it doesn't appear to be smooth. Once the eye is clear or I see flaking, I'm going to stop.

[areich]

You will see that the words billon and silvered are links and take you to Numiswiki, with an explanation of the terms.

[SC]

Billon = bronze alloy with a fair amount of silver added (usually 20-25% or more), or conversely silver alloy with a whole lot of bronze added - very low purity silver.

Silvered = bronze coin (any alloy content) coated with a layer of silver (either added on to the bronze or brought out from some silver within the the bronze alloy chemically).

Shawn

[Mayadigger]

Ave!

Fireproof - The yellow bits seen in your photo is the 'silvering', the dark parts is where it's come off the bronze/copper.

From Shawn -

What you have remaining appears to be what I called "stained" silvering.  While most of the dirt is off it appears to still have a very thin but hard clay-like dirt layer on the silvering.

You might be able to clean this off by soaks in distilled water, with or without washing soda, and very gentle brushing with a soft toothbrush.  Just a plain soft toothbrush not a stiff, cut-down toothbrush and light circular motions.

You may be able to assist this by gentle scraping with a toothpick as well.  One of the thicker round toothpicks either with its point or cut like a chisel.

Finally you may be able to clean the silvering with a scalpel or exact blade.

HOWEVER, there are caveats.  These techniques work well when the silvering is intact. 

With yours some of the silvering is gone, especially from the high parts.  This could be just wear and the rest is stable, or it could be a sign that it is ready to flake off everywhere!

So be very careful and stop at the first sign of flaking.

Also I would not use the scalpel method until a) you are sure of yourself, and b) you have a stereo microscope to do it at 10x or 20x magnification.

Shawn

As Shawn mentions, silvering such as seen on this coin can be very fragile. I wouldn't use any mechanical tool such as a dental pick, toothpick, or even a dried rose thorn on this coin. Instead, I'd use PreLim, an extremely gentile abrasive rubbing compound to remove the yellowness to reveal the silvering. In this case, by hand, rather than in a Dremel tool.

Also, Fireproof, if your coin is still in DW, remove it and let it dry. Wet never helps helps delicate silvered coins, but rather exacerbates the issue.

Best regards,

Kevin

[fireproof]

Thanks for the tip Shawn, it actually has been sitting dry for several days now. I read somewhere else that dw was bad so I didn't put it back in. I'm working on some other coins in the meantime. I am kind of annoyed now though. The other Licinius II coin I have is not silvered (this is good) but because of the way the coins were packaged when they were shipped to me, some of the silvering rubbed off Licinius I to the crusty parts of Licinius II! So this coin could have had more silvering but due to improper packaging it now looks like it does...