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 Replies: 9 / Views: 4,284 |
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Pillar of the Community
United Kingdom
3626 Posts |
Can anyone tell me what causes this>
I have it on my Diocletian (see Bargain Basement thread) and it seems to have more every time I look at it.
It is a shame because the coin was silvered and to remove the deposits would ruin the silvering. The bright green is quite attractive in it's own way.
Will the malachite continue to develop?
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Valued Member
United States
69 Posts |
That "malachite" is very likely verdigris. And it may very well continue to grow and damage more of your coin. http://en.wikipedia.org/wiki/VerdigrisLook for Verdi-chem (which used to be called Verdi-Care) to treat it. There are posts on this forum and other forums about its use and success if you search for them. The developer of Verdi-chem, poster BadThad, posts here and also on CoinTalk. http://www.wizardcoinsupply.com/pro...di-care.html |
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Pillar of the Community
 United Kingdom
3626 Posts |
I have verdi-care and it is not BD. This is a bright green solid deposit and quite different. I have read that it is referred to as malachite.
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Pillar of the Community
United States
1234 Posts |
Malachite is an ore of copper, it is mined and processed to produce copper metal. When copper decays and returns to the "rusted" ore state it can be called malachite again. In coin circles the "Rust" or decay of copper is called verdigris, in a few hundred years, or a little less if the humidity and other conditions are right that coin could be re-processed into copper. Verdigris is a metal disease and it is highly contagious to other copper coins. ** copper does not rust, that is why I put it in quotes.  |
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Pillar of the Community
United Kingdom
3626 Posts |
Definitely not verdigris. I have dealt with the powdery BD type, but this is quite different. It is rock solid. I can't find the link to the article I found on the internet, not that I understood it :)
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Pillar of the Community
United States
1234 Posts |
There is no picture of that coin on this thread, I have no idea what the "Bargain Basement thread" is I've tried to look it up on the 'Search Coin Community' option and have not found it.
I have no idea.
Good luck.
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Pillar of the Community
United Kingdom
3626 Posts |
Pics are not brilliant, the green is bright green.
www.coincommunity.com/forum/topic.asp?TOPIC_ID=170991
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Pillar of the Community
United States
1045 Posts |
Here is the coin in question:   |
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Pillar of the Community
United States
4973 Posts |
that's verdigirs...BD (the soft stuff) is different ...soft, as you mentioned. if it doesn't come off easily with a fingernail scrape, it isn't much to worry about I don't think.
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Pillar of the Community
United Kingdom
3626 Posts |
Thanks Chris. The photos don't show it properly. It is a bright shiny green. Some of it can be picked off but I am going to leave it as it is. It has had a coating of verdi-care and is going for a bake at some time.
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Replies: 9 / Views: 4,284 |
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Posted 02/27/2014 2:21 pm
