| Author |
 Replies: 27 / Views: 3,598 |
|
Pillar of the Community
United States
2669 Posts |
Hi all.. I was wondering if anyone had any pointers on how to get this stuff off this coin. Will distilled water help to start? Thanks for any help. ![How-To-Get-Gunk-Off-[warning:-Disturbing-Pictures!]](http://i242.photobucket.com/albums/ff297/xyshift/AU1914Obv.jpg) ![How-To-Get-Gunk-Off-[warning:-Disturbing-Pictures!]](http://i242.photobucket.com/albums/ff297/xyshift/AU1914Rev.jpg)  Edited by xshift
06/12/2008 6:01 pm
|
|
|
|
Pillar of the Community
United States
2177 Posts |
Mineral oil may work better than distilled water but it only get some off. The coin is rotting. Put it in a small jar and cover the coin with the oil and let sit for a year or longer. And find other coins to keep you busy while this one soaks.  |
|
Pillar of the Community
Australia
2830 Posts |
G'day,
the reverse seems to have gunk on it; but the obverse looks like the metal of the coin has been invaded. If I'm right about that, then it's too late to save this coin, so you may as well use it as a guinea-pig.
Any idea with circumstances &/or environment led to this sad state ? Has it been stored in plastic ?
I've never tried it myself, but our Seppo friends seem fond of acetone for the really tough cases.
You ought to put a warning in the subject:
"this post includes photos that will offend forum-ers"
Peter
|
|
Pillar of the Community
 United States
2669 Posts |
I'm sorry Peter.. I, too, was quite offended at the sorry state of this coin  ! I do not know how it got like this as I just got it. From the pictures it did not look near this bad, and to boot, the seller shipped it taped to a piece of paper  Quote:
You ought to put a warning in the subject:
"this post includes photos that will offend forum-ers" You're probably right.. Thingee, will the mineral oil stop the rot? Mineral oil as in what kind? I also have other oil here (everything from coconut to sunflower) - I was going to test their pH and see if any were useable like EVOO. But.. will oil STOP the rot? I want to save as much as possible without ruining it.. it's my first early Australian coin. |
|
Pillar of the Community
United States
5318 Posts |
Judging by the colors, I think I see hematite on the coin which suggests a ferrous object corroded next to its surface. It sounds odd, but sometimes bronze corrosion bonds with steel corrosion--maybe a chemist can explain that.  In either case, I'm saddened by this coin, and I don't think it can be restored to a collectible grade. From the looks of it, someone already tried cleaning too. Wait...somebody sold that coin? Huh. If you want a decent Aus Halfpenny, I'll trade you for something...not a 1914-H though.  Edited by KurtS
06/12/2008 6:36 pm
|
|
Pillar of the Community
Australia
2830 Posts |
G'day, quote: "will oil STOP the rot?" the theoretical answer to your question is like this: Most corrosion involves oxygen; removing the coin from sources of oxygen will arrest its deterioration; the obvious source of oxygen is the atmosphere; water contains dissolved oxygen, so that is unsuitable; most oils ought to be OK - but pH is an issue, which you seem to be aware of. I've heard it said that olive oil is suitable in this regard. The following link may be helpful: http://triton.vg/cleaning.htmlI think your situation justifies "desperate measures". I can't see how you can make the situation worse: an ideal starting point for an "experiment". Peter |
|
Pillar of the Community
United States
5318 Posts |
Peter--right, my apologies for sounding rather downbeat. This is a case where a careful experiment may improve the appearance.  I'll just note there's some pretty complex chemistry going on with that coin, so the usual methods of reducing verdigris may not work. Edited by KurtS
06/12/2008 7:12 pm
|
|
Moderator
 United States
23503 Posts |
For those of you not familiar with the "Australian Language" there are some non coin terms you may not be familiar with above Quote:
but our Seppo friends seem fond of acetone Let me define Seppo As we know Americans are known as Yanks  Yank rhymes with Septic Tank Thus if you are a Yank the shortened version of Septic Tank is Seppo.  Now doesn't that make you fee all warm and fuzzy  |
|
Pillar of the Community
United States
2669 Posts |
Quote:
Wait...somebody sold that coin? Kurt.. should be: Wait.. somebody bought that coin? urgh.. Would love to trade you, but we're still waiting for you to pick something for trade #1 Quote:The following link may be helpful: http://triton.vg/cleaning.html THAT one needed cleaning?! I'm in real trouble! Alright.. pH tests tomorrow.. everything from the shea butter to the grapefruit extract (wouldn't THAT be interesting). Ok - anything initially? Soft toothbrush? Running water? Soft brass bristles? DREMEL? |
|
Pillar of the Community
United States
2669 Posts |
rggoodie.. LOL that's a great explanation. I need to go take a shower now. Maybe that's where this coin came from!
|
|
Pillar of the Community
United States
5318 Posts |
Quote:
Yank rhymes with Septic Tank...Thus if you are a Yank the shortened version of Septic Tank is Seppo The first time I've heard "Seppo" was this forum, and I think it's rather funny. Quote:
Now doesn't that make you fee all warm and fuzzy I'll just leave the explanation to Aussies visiting the states. Xshift, I know...I just sent you an email. I have a few extra AUS 1/2d and 1d if you'd like to trade sometime. Edited by KurtS
06/12/2008 8:11 pm
|
|
Valued Member
United States
161 Posts |
Tip: Be careful where you use the term Yankee in the U.S. It is not a term all Americans consider themselves by any means. In some parts the term "redneck" is more complimentary than Yankee.
|
|
Pillar of the Community
United States
2669 Posts |
 Quote:
In some parts the term "redneck" is more complimentary than Yankee. Not really, unless you're one, as well... in which case, you can get away with it. Otherwise, hope you have your Go-Go-Gadget-get-my-behind-outta-here-booster-rockets strapped on real tight! Of course, calling someone a Yank when you are both rednecks would indeed be fightin' words I'm going to go attack oils with pH strips now |
|
Pillar of the Community
United States
2669 Posts |
Kurt - yes that would be lovely! Answered your email - and I'd love some Aussie coins that don't have.. stuff.. eating away at them.
|
|
Pillar of the Community
Australia
2830 Posts |
G'day,
quote: "anything initially? Soft toothbrush? Running water? Soft brass bristles? DREMEL?"
- I'd start conservatively. I'd soak it for a week; then I'd rub it between my fingers, to see what might loosen. If I saw any progress, I'd repeat that.
When that method is exhausted, I'd use a wooden or bamboo toothpick to try to loosen the gunk.
I'd avoid using any metal implements until last resort.
On my scale of harshness, toothbrush would come after toothpick.
Peter
|
|
Pillar of the Community
United States
2669 Posts |
After a bit of research, it looks like I won't be able to measure the oil pH with these strips. Since oils are not water-soluble they aren't measured the same way. (Which is probably why none of them changed color when I dipped them in the oils! ) I don't usually test oils directly, just finished products, so this has been a learning experience. Out of the stuff that did test well, Lactic Acid and Citric Acid both scored pH of 1 as a low, with Sodium Hydrolymethylglycinate scoring a whopping 14 as the high. Lactic Acid is used to lower pH in cosmetics, so I'm not sure what it would do to the surface of the coin. Looks like veggie oils are still the way to go. I'll be back in a few weeks from a trip, so I'll let it soak while I'm gone, and will post back with any improvements. Thanks for everyone's help so far. |
| |
Replies: 27 / Views: 3,598 |
Posted 06/12/2008 5:37 pm
