Green Patina = "Var Degree" = poison ??????

This hobby is fun & enjoyable, but it is not tiddlywinks. Be safe!

Moderator: Site Moderator

Post Reply
Oxbo Rene
Site Donor
Site Donor
Posts: 468
Joined: Wed Jun 16, 2010 5:26 am

Green Patina = "Var Degree" = poison ??????

Post by Oxbo Rene »

I was watching this young man's video on making a copper plate and he states that the green patina that forms on copper (verdigris) is poisonous,
and thus the copper needs to be coated with tin before consuming anything that has been in contact with it.
http://www.youtube.com/watch?v=VGqv47-Q ... 3JY0OM3f5w" onclick="window.open(this.href);return false;" rel="nofollow
I was just wondering about it and perhaps someone here would care to comment about this subject, especially as it pertains to copper still inards etc, etc ...
He starts talking about it at Min # 1:12 .................
The video sometimes starts out past this minute mark so ya might have to grab the slider and drag it back to before min # 1:12
Tx's
Last edited by Oxbo Rene on Wed Mar 06, 2013 12:58 pm, edited 1 time in total.
It is not the matter, nor, the space between the matter,
but rather, it is that finite point at which the two meet,
that, and only that, is what is significant...........
(Of course, I could be wrong) ..........
Butterman
Bootlegger
Posts: 132
Joined: Wed Jan 09, 2013 7:28 am
Location: Seattle

Re: Green Patina = "Var Degree" = poison ??????

Post by Butterman »

Copper pipes have been used to supply water for many many decades and possibly even up to and past 100 years in some cities, let alone the thousands of years its been used for drinking vessels. Ive demolished lots of building and torn out alot of the copper in old building and most if not all the copper Ive torn out all had a green patina on the inside. So just form my empirical evidence I would consider it safe, tried and true.
On a side note my still does not build up any green patina on the inside.

Butterman

PS its kinda of interesting video, I sure do like his shear :>
Last edited by Butterman on Wed Mar 06, 2013 12:21 pm, edited 1 time in total.
MDH
Distiller
Posts: 1001
Joined: Tue Nov 29, 2011 4:33 pm
Location: Pacific Northwest

Re: Green Patina = "Var Degree" = poison ??????

Post by MDH »

The patina is copper hydroxide. Just react it with citric acid solution. Don't discard the blue liquid resulting from it, it's useful.
The still is not a liar. Mash and ferment quality is 99.9% of your performance.
Oxbo Rene
Site Donor
Site Donor
Posts: 468
Joined: Wed Jun 16, 2010 5:26 am

Re: Green Patina = "Var Degree" = poison ??????

Post by Oxbo Rene »

This is a little more I came up with --->
http://en.wikipedia.org/wiki/Verdigris" onclick="window.open(this.href);return false;" rel="nofollow
"As verdigris consists of various poisonous copper compounds, one should always wash one's hands after handling"
And the dictionary definition -->
http://www.merriam-webster.com/dictionary/verdigris" onclick="window.open(this.href);return false;" rel="nofollow

MDH = It would be kinda nice if you'd elaberate a bit more on the usefullness of the blue liquid .......
It is not the matter, nor, the space between the matter,
but rather, it is that finite point at which the two meet,
that, and only that, is what is significant...........
(Of course, I could be wrong) ..........
heartcut
Site Donor
Site Donor
Posts: 2781
Joined: Tue Mar 29, 2011 9:31 am
Location: Houston, Texas

Re: Green Patina = "Var Degree" = poison ??????

Post by heartcut »

Copper carbonate (the regular fresh water verdigris) is insoluble in water and ethanol.
Copper chloride (the salt water variety) is a little bit soluble in water and/or ethanol but will precipitate as a solid when the liquid evaporates.
Both are toxic to humans, so don't scrape some off and eat it.
heartcut

We are all here on earth to help others; what on earth the others are here for I don't know.

W. H. Auden
aknewb1s
Novice
Posts: 44
Joined: Sun Feb 10, 2013 9:22 am

Re: Green Patina = "Var Degree" = poison ??????

Post by aknewb1s »

MDH wrote:The patina is copper hydroxide. Just react it with citric acid solution. Don't discard the blue liquid resulting from it, it's useful.
Useful for what?
Oxbo Rene
Site Donor
Site Donor
Posts: 468
Joined: Wed Jun 16, 2010 5:26 am

Re: Green Patina = "Var Degree" = poison ??????

Post by Oxbo Rene »

Yeah, really ! ! ! ! ????
It is not the matter, nor, the space between the matter,
but rather, it is that finite point at which the two meet,
that, and only that, is what is significant...........
(Of course, I could be wrong) ..........
Gaztops
Bootlegger
Posts: 129
Joined: Mon Jul 09, 2012 12:21 pm
Location: Old England UK

Re: Green Patina = "Var Degree" = poison ??????

Post by Gaztops »

I do a lot of metal detecting as a side hobby, and quite few coins of copper and bronze value have verdigris on them. According to the metal detecting fraternity the last thing you should do after handling such an item is to put your fingers near your mouth.

Some call it patina others poison, is it worth the risk. I value the insides of my stomach and don't even eat Indian food let alone green decomposition. I check my pipework from the pot to the liebig for verdigris and do a vinegar still clean out as required.
A man who doesn't read good books has no advantage over a man who cannot read.
Post Reply