Ack! My S-215 DBLC has turned black!

Aotearoa

The first set of photos show what the coin looked like six years ago when I bought it. The next set of photos were taken today. What has happened and what corrective action can I take? (I’m afraid I know the answer to the last part.) Other coins stored with this one have not suffered at all.

Yes, this was a details coin even before the black took over but it’s a minor key to the series and I’m not likely to find an affordable replacement. I’m actually quite distraught…

thebeav

MY first thought was a probable acetone bath may be in order, but the 'lightness' on the high points says that the coin may have originally had some sort of coating applied.
No one can blame you for being upset. I hope you figure out a good solution.

Namvet69

Agree that it's weird that the highest details are showing "wear". Any possibility this coin was exposed to subtle friction? Over the course of 6 years.

PerryHall

Where was this coin stored---home safe, bank SDB, basement, etc? What kind of holder was it stored in?
I don't collect copper coins but I've read that a long soak in olive oil is frequently used to remove crud from old copper coins.

Cougar1978

Appears to be reaction to atmosphere over time. Perhaps our hosts can help with conservation service.

Even if it gets details grade there are many who may buy it to fill that space in collection. Or a problem coin dealer may purchase.

Walkerguy21D

The original photos look like it was soaked in something and not properly removed. My guess is that reacted or turned over time. Hopefully not eaten into the surface.

I’d start with acetone, then move on to Blue Ribbon or Care or something stronger if warranted.

Manifest_Destiny

I agree with Walkerguy. It looks like it was soaked and not properly rinsed which caused the reaction.

jfriedm56

The surfaces look pitted in your original pictures. Agree with others that there must have been residue left from the most recent treatment (6 years ago), and has reacted with the metal over the ensuing years. Looks like a metal detector find.

jmlanzaf

I don't think it was soaked in a solvent. Looks tho me more like it was coated in something that is still on the surface.

lkenefic

My 2 cents worth... it looks like the coin had porous surfaces initially and might have had some corrosion removed... by an olive oil soak or maybe something more aggressive... but whatever treatment was used, it left the coin with a bright copper color which is a big red flag for early copper (indicates cleaning). Applications of baking soda with hot water, or use of sulfur containing compounds (like leaving the coin in a baggie with a crushed hard boiled egg) will cause the formation of copper sulfides which darken the coin and hide the "cleaned copper" color.... which is where this coin sits currently. At this point, I'd be hard pressed for a solution to bring back the more pleasant medium/dark brown color. Acetone can't hurt but I doubt it's going to be very effective in lightening the color. Blue Ribbon, if you can find it, might be helpful but I've mostly used it to remove verdigris and stabilize anything that looks like active corrosion. Best of luck and please let us know if you find anything that works... Best, Leo...

Aotearoa

The coin was purchased from a reputable early copper dealer (who used to post here occasionally) and has been in a Lighthouse Quickslab since I bought it. No friction. This particular coin didn't meet the value threshold for the SDB. Other coins purchased from the same dealer, self-slabbed the same way and stored the same way have not met the same fate.

I really appreciate the thoughts and suggestions. I'll start with acetone and olive oil and go from there. Not a lot to lose at this point.

JBK

I see some areas of black encrustation on both obverse and reverse in your original photos (near the top). I suspect that it's current appearance is what it looked like at some point in the past, and some sort of treatment (olive oil?) made it look the way it did six years ago. In the years since then the original appearance has re-emerged, perhaps as the "treatment" has dissipated.

Just my uneducated opinion....

mark_dak

@lkenefic said:
My 2 cents worth... it looks like the coin had porous surfaces initially and might have had some corrosion removed... by an olive oil soak or maybe something more aggressive... but whatever treatment was used, it left the coin with a bright copper color which is a big red flag for early copper (indicates cleaning). Applications of baking soda with hot water, or use of sulfur containing compounds (like leaving the coin in a baggie with a crushed hard boiled egg) will cause the formation of copper sulfides which darken the coin and hide the "cleaned copper" color.... which is where this coin sits currently. At this point, I'd be hard pressed for a solution to bring back the more pleasant medium/dark brown color. Acetone can't hurt but I doubt it's going to be very effective in lightening the color. Blue Ribbon, if you can find it, might be helpful but I've mostly used it to remove verdigris and stabilize anything that looks like active corrosion. Best of luck and please let us know if you find anything that works... Best, Leo...

I'm not a copper guy but I agree that this one probably had some type of environmental damage from the outset and whatever was done to it was not a professional job. At least it's not a crazy expensive coin.

Good luck in your attempt to breathe some eye appeal back into your coin.

Mark

PerryHall

Would it make sense to carry it for a while with other pocket change to let it wear down a little and to lighten the color some? It will always be a details coin but it could improve its appearance some.

tcollects

@PerryHall said:
Would it make sense to carry it for a while with other pocket change to let it wear down a little and to lighten the color some? It will always be a details coin but it could improve its appearance some.

I've tried this a million times and it never works, not yet anyway

Aotearoa

@JBK said:
I see some areas of black encrustation on both obverse and reverse in your original photos (near the top). I suspect that it's current appearance is what it looked like at some point in the past, and some sort of treatment (olive oil?) made it look the way it did six years ago. In the years since then the original appearance has re-emerged, perhaps as the "treatment" has dissipated.

Just my uneducated opinion....

I noticed the black gunk - especially over the TY in Liberty - when I bought the coin and thought about giving it an acetone soak then. I don’t know if it would have made a difference but, in retrospect, I should have given it a go.

Aotearoa

@mark_dak said:

@lkenefic said:
My 2 cents worth... it looks like the coin had porous surfaces initially and might have had some corrosion removed... by an olive oil soak or maybe something more aggressive... but whatever treatment was used, it left the coin with a bright copper color which is a big red flag for early copper (indicates cleaning). Applications of baking soda with hot water, or use of sulfur containing compounds (like leaving the coin in a baggie with a crushed hard boiled egg) will cause the formation of copper sulfides which darken the coin and hide the "cleaned copper" color.... which is where this coin sits currently. At this point, I'd be hard pressed for a solution to bring back the more pleasant medium/dark brown color. Acetone can't hurt but I doubt it's going to be very effective in lightening the color. Blue Ribbon, if you can find it, might be helpful but I've mostly used it to remove verdigris and stabilize anything that looks like active corrosion. Best of luck and please let us know if you find anything that works... Best, Leo...

I'm not a copper guy but I agree that this one probably had some type of environmental damage from the outset and whatever was done to it was not a professional job. At least it's not a crazy expensive coin.

Good luck in your attempt to breathe some eye appeal back into your coin.

Mark

Not crazy expensive but seemingly rarer than the R.4 rating would lead one to believe. I also really like the late die state.