Tarnish Or Blackening Around Lugs

[michael999]

Hello...Could any member tell me if there is away way to remove Tarnish or Blackening the comes around the lugs and sometimes moves to the edge of a badge close to where the lugs are attached..
I am not sure I am calling this darken around the lugs the correct name..I know it is not Verdigris which is greenish in color this is black must come from the material that has been used to attach the lugs to the badge..
Maybe it is Verdigris that has advanced beyond cleaning..
Any information I could get on what this is and if it can be cleaned would be appreciated...

Thanks Mike

[2747andy]

Originally Posted by michael999

Hello...Could any member tell me if there is away way to remove Tarnish or Blackening the comes around the lugs and sometimes moves to the edge of a badge close to where the lugs are attached..
I am not sure I am calling this darken around the lugs the correct name..I know it is not Verdigris which is greenish in color this is black must come from the material that has been used to attach the lugs to the badge..
Maybe it is Verdigris that has advanced beyond cleaning..
Any information I could get on what this is and if it can be cleaned would be appreciated...

Thanks Mike

Mike,
To be honest if it is not doing any harm I would leave it there as it adds to the authenticity

Andy

[michael999]

Thank-You Andy...Just out of curiosity what causes this..Is it the material that
was used to attach the lugs to the back of the badge that just oxidized

Thanks Mike

[elgee45]

Hello Mike,

Verdigris is formed when a small amount of CO2 in moist air forms carbonic acid and attacks the copper to form copper carbonate - green in colour. The black coating on your copper lugs is cupric oxide, formed by the reaction between the oxygen in the air and the copper. It takes much longer to form than verdigris, and I would agree with Andy that it's a good indicator of age and authenticity and should be left alone. If you don't like it, a small amount of juice from a fresh lemon will remove it, but be careful, it will also remove the patina from your badge - I wouldn't recommend it. Hope this helps.

Lawrence

[michael999]

Thank You Lawrence..No I will not try and remove it...It is very interesting to know what it is and what causes it..I have been collecting for about 5 years and have many badges and never realized what it was and what makes it show up on the badge..You information is much appreciated...

And Thank-You for taken the time to answer my question...
Andy always appreciate your input I read a lot of you threads you are very knowledgeable on military badges. Wish I had about 10% of you knowledge..

Thanks again Andy and Lawrence..

[runic1901]

Hi Lawrence,
I'm principally a button collector, and have acquired a few which have verdigris, to varying degrees.
I've been told: -
1. there is no way to remove it fully, and
2. that it can affect other brass items (buttons)
Are these statements true, or do you know of a way to remove verdigris without damaging the remaining silver plated or gilded surface.
Regards, Tony

[elgee45]

Tony, I don't think there's any way to remove verdigris that won't affect the metal to some extent. It's a trade-off, also the verdigris may have eaten its way into the metal in bad cases - not much you can do about that. The copper salts that form verdigris are not soluble in water, but will react with weak acid solutions to form soluble salts that will wash off in water. You need to take great care and use very small quantities of weak acid, such as the citric acid from a lemon. Apply with a cotton bud and try to keep the acid from bare metal areas - don't try and rush it. When you're done wash thoroughly with water while brushing with a soft brush - old toothbrush . . .

There are some posts I recall from a while back that discuss methods of protecting metal badges from oxidation with various products, the names of which escape me. Might be worth doing a search. Hope this helps.

Lawrence