Author Topic: Returning collectibility to coins  (Read 1651 times)

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Offline Alan Glasser

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Returning collectibility to coins
« on: April 23, 2013, 07:47:26 PM »
Hello everybody. I hope this note finds everyone well.

I am still going through a few boxes of "accumulated coins" from my early years and the Australian coin in the photo above is worthy of resurrecting, in my opinion. I have no idea how, however. I don't want it to appear cleaned, but I would like to remove the accumulated greenish gunk (it is almost a "build up" of something and I don't think it is PVC). Any suggestions would be appreciated. I don't collect Australian pennies (I found a nice 1940, 1944 and 1943 along with the 1922 in the photo in the box today...I hope this afternoon to determine mints. I am confused as to 1943 "with I or without I" ...WHAT I???) Anyway...maybe I'll list them on the trade column...

Back to the purpose of the post. If anyone has any suggestions as to how to "restore" the 1922, I would be most grateful. I hate to leave it as it is as I am wondering if it is continuing to degrade.

The Netherlands Zinc coin is one example of may zinc pieces I have that have turned white. I am curious as to the metallic reaction that causes this and if it also can be reversed. How does one work to approve the appearance of zinc coins without altering the original surfaces? 

Neither of these coins has been housed in PVC while in my ownership. They were, along with many other world coins, just kept in a cardboard box, not in holders. Could the Australian cent appearance be the result of contact with other metals or chemicals in the cardboard box?

Many thanks. Alan in Massachustts





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Offline Figleaf

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Re: Returning collectibility to coins
« Reply #1 on: April 23, 2013, 08:38:29 PM »
The white on the zinc is oxidation. Zinc oxide is powdery. You can rub it off easily. Zinc does not become shiny again, so even if you wanted to, you couldn't do harm.

The green on bronze is also oxidation, of course. Remove it with soft cloth, drenched in olive oil. If it is thicker than I think it is, give the coin a prolonged olive oil bath (a month or two) and rub off the oxidation. If it doesn't want to be rubbed off, convince it with a wooden toothpick. You will get "clean spots" where the rust has been. The olive oil will darken the spots somewhat and time and pollution will do the rest. Grin and bear it.

Peter
An unidentified coin is a piece of metal. An identified coin is a piece of history.

Offline Alan Glasser

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Re: Returning collectibility to coins
« Reply #2 on: April 23, 2013, 08:43:14 PM »
Hello Peter and thanks.

The Australia penny will receive an olive oil on a soft cloth bath this evening when I get home from my piano lessons.

Whitish powder oz zinc...I think I will use a spare eyeglass cloth.

Again, thanks.

Alan

Offline Prosit

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Re: Returning collectibility to coins
« Reply #3 on: April 23, 2013, 10:25:34 PM »
An interesting side note...zinc oxide in very small concentrations is used in some diaper rash formulas  :)

It is widely used as an additive in numerous materials and products including plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first aid tapes.

It is an interesting material when not on coins.

Dale

Offline Alan Glasser

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Re: Returning collectibility to coins
« Reply #4 on: April 23, 2013, 11:27:44 PM »
Hey, Dale.

I never thought of that. Zinc Oxide is used in certain skin irritation creams too I believe...now that you mention it. Amazing the things we learn here!  ;)

Alan

An interesting side note...zinc oxide in very small concentrations is used in some diaper rash formulas  :)

It is widely used as an additive in numerous materials and products including plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first aid tapes.

It is an interesting material when not on coins.

Dale

Offline malj1

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Re: Returning collectibility to coins
« Reply #5 on: April 23, 2013, 11:55:09 PM »
I am confused as to 1943 "with I or without I" ...WHAT I???) Anyway...maybe I'll list them on the trade column...


Part of the 1943 issue of Australian pennies was minted in India these bear a small 'I' below the bust.

Malcolm
Have a look at  my tokens and my banknotes.