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 Replies: 47 / Views: 12,456 |
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Pillar of the Community
United States
6383 Posts |
This is an important topic that should be of interest to all collectors. I purchased this AU Seated dollar knowing it had been cleaned. The price was low enough to be attractive. ANACS gave it an "AU details, net EF45 cleaned" grade. Although the reverse is only slightly affected by the cleaning, the obverse has many fine hairline scratches that are pretty noticeable. Always check each prospective purchase carefully for hairlines! Tilt the coin under an incandescent or halogen light. Hairlines can hide until you get the angle and lighting just right; then they jump out at you.   |
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Pillar of the Community
United States
651 Posts |
SuperDave,
I'm still learning some detection methods and was hoping you could define what "smoked" means or how its done.
Thanks,
Ken
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Valued Member
Philippines
52 Posts |
I would like to add some of my observations about using different variety of cleaning agents to silver coins, below are samples I did using 3 types of cleaning agents, Acetone, Mild Battery solution (H2So4) & Thiourea. I've used these US-Philippine 20 centavos as my test subjects. The top coin is never cleaned but an AU 20centavo Coin, first coin from the right is dipped in Thiourea, middle is dipped in acetone while last one on the left is dipped with Mild Battery Solution.   In my humble opinion, thiourea seems to dull this type coins further, probably it doesn't react well with othe metals present in this coinage  . Acetone seems to do the job just fine however it doesn't rid the stains completely but it obviously retains the mint luster. Battery Solution is highly acidic but it does clean every dirt and stains off the coin plus it gives a brilliant white shine, it didnt corrode the coin as I was anticipating.  |
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Pillar of the Community
Belgium
2078 Posts |
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Valued Member
United States
228 Posts |
I am not sure how it was cleaned,I just know it was.   Fishnwidow |
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Pillar of the Community
United States
819 Posts |
Is the Acetone mentioned in the posts above the same quality, strength as found on the shelf in the paint section of hardware stores; along with paint thinner, turpinetine, etc?
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Pillar of the Community
Belgium
2078 Posts |
My acetone comes from a Belgian supermarket at 2 euro a bottle
As I understand it there are only two kinds
Supermarket and pro analysis which costs probably 20 times more
( You get a purity certificate and a glass bottle instead of a plastic bottle )
Oh yes and my surgical gloves do'nt seem to have a problem with acetone .
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Pillar of the Community
Belgium
2078 Posts |
Moving on to dipped or not My mentor told me that dipped coins against any true reference will show yellow because of the bite of the dip on copper He also told me that ten years of time will make the difference go away  Dipped  |
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Pillar of the Community
Belgium
2078 Posts |
Undipped MS64+  |
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Pillar of the Community
United States
819 Posts |
Fishnwidow, your SLQ reminds me of the effect obtained by gently rubbing a coin with a kitchen spice; I can't seem to remember the name of it but it is a very, very, fine white powder..not baking soda...I am thinking Tumeric or something like that...kitchen is not my home and can't rememeber the name, will browse the spice rack tomorrow and see if anything rings a bell. My mother used back in the 50's to show me how to clean a coin and make it "shiny." It was almost like Talc powder it was so fine, anyone know of it?
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Pillar of the Community
United States
819 Posts |
cruise d down the isle of spices at the local grocery during lunch, I think I remember the stuff now, it was cream of tartar; its really not a cream but a very fine powder
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Pillar of the Community
United States
6383 Posts |
Speaking of cleaned coins, I think I just spotted a primo example. Heritage is running an internet auction right now. It's their "2007 April Dallas, TX Final Session", auction #451. They have an 1874 Seated Liberty half dollar graded PCGS 50 listed as lot #7590. I tried to copy an image to post but couldn't; maybe the image is secured somehow. Anyway, this coin looks to me like it is severely hairlined from a harsh cleaning. I wouldn't even attempt to submit a coin like this for grading because it would surely be rejected. So, how did this one get into the slab? If anyone is interested, please go to http://coins.ha.com and check out this listing. I would be very interested in hearing what other forum members think about this coin. Thanks! |
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Pillar of the Community
Belgium
2078 Posts |
You mean this one  |
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Pillar of the Community
Belgium
2078 Posts |
Reverse  |
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Valued Member
United States
70 Posts |
This one has old cleaning. I bought it anyway, because I liked it & the price was right...  |
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Replies: 47 / Views: 12,456 |
First Page
Posted 04/08/2007 02:54 am
