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Replies: 18 / Views: 2,256 |
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Valued Member
Australia
372 Posts |
If they are proofs...... pretty sure they were done in India in 1965. They were short lived because the Mint/Government put a stop to doing proof restrikes. That's the short version.  Nice looking coins though.
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Valued Member
United States
111 Posts |
They sure are pretty. But, how common is it for rainbow toning to appear on both sides, so dramatically? I personally have not seen such even and similar toning on both sides of a US coin. Is it common for Australian coins?
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Pillar of the Community
Australia
3831 Posts |
If I'm not mistaken, proof Aussie copper coins tended to tone and many of them that I saw with the dealers here have slight hues of blue and green with them. But that's a nice one there.
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Pillar of the Community
Canada
1267 Posts |
Immpossible to tell from the scans provided whether there are real or cooked. I see some shadowing around the devices which is a good sign of natural toning, but the colors as they appear on my monitor are funky. Can't tell. 
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Pillar of the Community
United States
830 Posts |
I like the color on those. They look very much like the toning I've seen on proofs from the U.K. and South Africa.
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Pillar of the Community
United States
7123 Posts |
quote: Okay, okay, I know they are Australian, but we'll just pretend that they are U.S. coins and then this topic can stay here,
There is no restriction that I'm aware of that prohibits Australian coins from the main coin forum ? The coins are beautiful !! Copper can tone to these colors natually if they live in the right environment long enough. These ones however look AT to me since the natural process normally begins at the rim and works inwards ,, but they are pretty. Metalman
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Moderator
 United States
23522 Posts |
quote: Immpossible to tell from the scans provided whether there are real or cooked. I see some shadowing around the devices which is a good sign of natural toning, but the colors as they appear on my monitor are funky. Can't tell.
That makes for a nice segue into my question - does the composition and/or climate make a difference in how these coins might tone? On US copper, such colors would be cause for suspicion, although our coins are much more likely to be victimized by coin chefs than Australian issues. Subjective opinion? Wonderful coins. I'd like to be second in line after Dockwalliper, please. 
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Pillar of the Community
United States
4589 Posts |
wow those are very Beautiful Proof or not
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Pillar of the Community
United States
1203 Posts |
Very nice Snooba, and just keep in mind that in the last 63 years, anything might be possible with these coins. That is a long time for them to 'not' have some toning of some kind appear. So why not have it be the colors that they display!
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Pillar of the Community
Canada
1267 Posts |
quote: That makes for a nice segue into my question - does the composition and/or climate make a difference in how these coins might tone? On US copper, such colors would be cause for suspicion, although our coins are much more likely to be victimized by coin chefs than Australian issues.
Composition and climate both play a role in toning. Hot, humid weather accelerates toning.........it is believed the recent Battle Creek Hoard came from such an environment and explains the vibrancy and intensity of the colors. Also, silver tones differently than gold, copper or nickel so the actual composition of a coin will yield different results. That's why the American silver eagles tone so quickly............they are almost pure silver. Another factor that plays a huge role in how a coin will tone is in the planchet preparation and what type of rinse was used. Apparently this is why Peace dollars tone so poorly compared to their earlier Morgan counterparts.......and why 1921 Morgans are also rarely found with even toning. Different rinse. Hope this helps a little.
Edited by hadleydog 01/28/2007 6:04 pm
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Pillar of the Community
United States
2177 Posts |
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Pillar of the Community
 Australia
1360 Posts |
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Pillar of the Community
Australia
1295 Posts |
From a chemical point of view toning will depend on how the coins were stored and the crystalline structure of the coined metal. Generally we are conditioned to think that toning does start from the outside and this is due to the method in which the vast majority of coins are stored:
1. In albums 2. In rolls 3. In 2x2 holders (maybe less likely, I am not sure 2x2's have been around)
In each of these cases the interface between the coin and the chemically reactive holder is around the edges and thus toning is more than likely to start around the edges. Hence the term 'album toning' or 'roll toning'.
However, from a mettalurgical point of view toning can happen in areas of highest stress on the coined metal. In these areas the crystalline structure is finer and with more crystal/crystal interfaces it can result in areas of the coin thatc will tone more than others. Take some images we've seen on here of bag toned morgans, in this case the toning is across the surface the coin and doesn't seem to have started at the edges. This is because the surface of the coins was in contact with a chemically reactive coin bag.
The other factor to take note of here is that Australian pre-decimal proofs were often struck with business strike dies that were hand polished. In the case of the 1955/56 penny proofs this can lead to strange toning and luster breaks due to the die polishing marks in the fields.
To be perfectly honest, with coins as rare as these (and pre-decimal proofs this early are extremely rare) I wouldn't be bothered too much even if they were AT. It will be a long long long time before coins like them come back onto the market.
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Pillar of the Community
 Australia
1360 Posts |
Thanks, Susan, for uploading the photographs for me!
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New Member
United States
20 Posts |
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Replies: 18 / Views: 2,256 |
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