Olive Oil to the rescue, extra virgin, of course...........................
keets
Posts: 25,351 ✭✭✭✭✭
Well, I bought this medal on eBay about six months ago, it's HK-468 and listed as "Rare" by Mssrs. Hibler and Kappen with a twist----in my years of looking at/for SC$'s I'd never seen an example listed before. Upon first inspection it looks like it's companion HK-467, but you'll notice that the date on the upper right reverse is 1934 and not 1933. A subtle difference but isn't that what us collectors live for?? Anyway, it probably went unnoticed because it had no reference to the Reverse date and no reference to the HK number in the title or description that went with the listing, so a quick glimpse meant nothing. I believe I paid about $35.
When the item arrived it had some obvious shellac or similartype material covering almost the entire surface, not evident in the pictures but also not very troubling upon first inspection. I reasoned it could be removed with acetone so I e-mailed the seller to seal the transaction and placed the medal in a flip for a bath when I had the time. When that time arrived the shellac came off quickly but left a white stain in the area which now appears dark, my first thought being PVC or some other corrosive. Not knowing what to do and not wanting to risk further damage I placed the medal in a container with some Olive Oil and conveniently forgot about it until last week. I happened to be tidying up the basement and found the container, opened it and was pleasantly surprised that the whiteness had vanished only to be replaced by what we see in the picture as a dark band of color. Sadly, there is in fact some damage at the rim where the metal has been etched, but aside from that it seems intact as struck.
I gently washed it in tap water with some dish detergent to remove the oil since I freaked at the thought of what acetone might do!!! Now I'll rinse it thoroughly with distilled water, blow dry with canned air and stick it in a flip for a short spell before it goes off to NGC via NCS for long term storage in a capsule from either company. My questions, cause I always have question, are these:
1. Do you think the medal was in fact damaged by a PVC residue from whatever it was that had been on it?? If not PVC, then what would cause that on bronze??
2. What caused it to darken as it has, is that a result of the Olive Oil soaking into the pores and removing the contaminants to reveal clean metal?
3. I see the medal as an AU, will NGC see it the same and holder it or do you think NCS will determine it's too impaired and just authenticate it?? I assume option #2.
4. Have you ever had similar results with copper and Olive Oil?? This was my first soak session, but I'm sold!!
Thanks and enjoy the medal for what it is.
Al H.
When the item arrived it had some obvious shellac or similartype material covering almost the entire surface, not evident in the pictures but also not very troubling upon first inspection. I reasoned it could be removed with acetone so I e-mailed the seller to seal the transaction and placed the medal in a flip for a bath when I had the time. When that time arrived the shellac came off quickly but left a white stain in the area which now appears dark, my first thought being PVC or some other corrosive. Not knowing what to do and not wanting to risk further damage I placed the medal in a container with some Olive Oil and conveniently forgot about it until last week. I happened to be tidying up the basement and found the container, opened it and was pleasantly surprised that the whiteness had vanished only to be replaced by what we see in the picture as a dark band of color. Sadly, there is in fact some damage at the rim where the metal has been etched, but aside from that it seems intact as struck.
I gently washed it in tap water with some dish detergent to remove the oil since I freaked at the thought of what acetone might do!!! Now I'll rinse it thoroughly with distilled water, blow dry with canned air and stick it in a flip for a short spell before it goes off to NGC via NCS for long term storage in a capsule from either company. My questions, cause I always have question, are these:
1. Do you think the medal was in fact damaged by a PVC residue from whatever it was that had been on it?? If not PVC, then what would cause that on bronze??
2. What caused it to darken as it has, is that a result of the Olive Oil soaking into the pores and removing the contaminants to reveal clean metal?
3. I see the medal as an AU, will NGC see it the same and holder it or do you think NCS will determine it's too impaired and just authenticate it?? I assume option #2.
4. Have you ever had similar results with copper and Olive Oil?? This was my first soak session, but I'm sold!!
Thanks and enjoy the medal for what it is.
Al H.
0
Comments
I suspect something migrated out of the shellac to cause the whiteness and this reacted with something to cause the darkening. Shellacs are usually some man-made concoction now days and can contain almost anything.
Buying top quality Seated Dimes in Gem BU and Proof.
Buying great coins - monster eye appeal only.
<< <i>Sam, i realize you don't necessarily look at or collect these, but coming from a little closer to Chicago have you by chance seen one dated 1934?? >>
No. That that I recall. I don't even have the '33 yet though since I've never seen it cheap.
that's why i posed question #2. the remainder of the medal is the proper color, only the area that was damaged has darkened.
Olive oil can and will turn rancid. It can and will make copper coins darker. Mineral oil is more gentle.
Mineral oil works best on copper coins. It can also remove light milky spots and streaking on silver coins as well.
Best to use mineral oil in business strike coins. Proof coins surfaces are quite fragile and best to stick with acetone or water.
Yet, circulated copper surfaces can darken as a result of the oil bath.
The problem with too rapid an evaporation bath is that it can leave subtle coloration with the copper surfaces whereas the steady dabbing and squeeze drying of the slow evaporating mineral oil with very soft tissue paper guards against the coloration streaks.
I've messed with old large cents that were in pretty bad shape- using olve oil and xylol.
If you take that medal and give it an acetone bath, I pretty much guarantee it will return to the white stain stage and look like it did before the olive oil soaking. Like you said, the oil just soaks onto and is adsorbed by anything porous enough to hold onto it. The oil hasn't cleaned or removed anything, just altered the appearance of the piece by adhering to the surface. Just like asphalt or concrete will look darker after a rain or throwing on some kind of oil. Acetone it and it will remove the oil and the darker appearance imparted by the oil.
I, too, would use mineral rather than olive oil. Seems like it would be safer.
I don't know what the piece looked like before the acetone, but my guess is that the shellac acted in a way similar to the oil and was masking some sort of corrosion.
Interesting piece. At first glance I expected a swastika under the eagle!
From one Al to another...