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Patina on copper

Jewelry Discussion
#1

i’m interested in trying some of the nontoxic recipes for creating
patina on copper that i have seen in messages lately. but i have a
few questions.

-pedro mentioned that a salt and water paste would create a patina on
copper. i have tried soaking the copper (wire) in the paste, but no
patina has developed. does the wire have to be exposed to the air
after the contact with the salt/water before the patina develops? is
it a matter of repeated exposures to the salt/water and air? how long
does it take for patina to develop with this?

-alma mentioned how her flux for lead-based solder created a
blue-green patina. how long does it take for the patina to develop?
i have treated some copper wire to the flux with zinc chloride, but
see just a hint of cloudiness on the wire. do i need to be patient?
do i need multiple applications? is the heat of the torch necessary
to see a rapid development?

-i have looked in tim mccreight’s complete metalsmith for patina
recipes. the green patina refers to ammonium chloride and says another
name for it is sal ammoniac. where should i look for this ingredient?
i have never purchased anything from a chemical supply place and hope
that sal ammoniac is something common that i can buy somewhere else.

i looked at the brain press page on ganoksin.com and found his book
"patinas for small studios." it sounds like just the thing i need.
the emphasis is upon common, safe ingredients…

thank you in advance for any advice you can give me. i should say
that i took one year of chemistry about 36 years ago. you get the
picture.

Jean Adkins columbus, ohio

#2

Use ammonia instead of water. The item can be fumed in this mixture
by suspending it over a bowl with the mixture and tenting it with a
plastic bag. Be careful not to get too heavy of a buildup. It will
flake off. Your metal should be very clean.

Marilyn Smith

#3

To do this you need also an open container of ammonia. Salt the
copper, and put it in a plastic bag with an open container of ammonia
overnight. This can be very fun if you put a mask on the copper to
create a design. Color will be brown to blue-ish. Usually more brown.

sal ammoniac. This is used to tin soldering irons too. You can get
some at a hardware store. I believe I have also seen it in the drug
store.

“patinas for small studios.”

Yes, this is a good one.

You can get a nice red color on copper by just using borax and a
torch.

Good luck and have fun!
Mary Barker, HPCU IT - MTS
@mary_barker
(650) or TN 857-7372
E-Fax 801-340-9408

#4

Did you clean the copper wire? Most wire is coated with a varnish or
shellac. To the salt, I would add vinegar or better (to me) ammonia.
The patina starts fastest if the wetted metal is exposed to the air
verses buries in the mix. Takes a couple of minutes (light patina)
to a day. Reapply if more color is needed.

    -alma mentioned how her flux for lead-based solder created a
blue-green patina.  how long does it take for the patina to
develop? i have treated some copper wire to the flux with zinc
chloride, but see just a hint of cloudiness on the wire.  do i need
to be patient? do i need multiple applications?  is the heat of the
torch necessary to see a rapid development?

The torch heat most likely burned off any coating. This takes time
and a bit of moisture. Heat tends not to speed this up.

-i have looked in tim mccreight's complete metalsmith for patina
recipes. the green patina refers to ammonium chloride and says another
name for it is sal ammoniac.  where should i look for this ingredient?
 i have never purchased anything from a chemical supply place and hope
that sal ammoniac is something common that i can buy somewhere else.

Chemical place as far as I know.

    i looked at the brain press page on ganoksin.com and found his
book "patinas for small studios."  it sounds like just the thing i
need. the emphasis is upon common, safe ingredients.... 

thank you in advance for any advice you can give me.  i should say
that i took one year of chemistry about 36 years ago.  you get the
picture.

Jean Adkins columbus, ohio

From the Orchid list: One of my favorite patinas is blue on brass.
Put a little ammonia in the bottom of a plastic container and suspend
the brass piece inside, cover and wait until the patina develops. You
can also add a little table salt for a slightly different effect. -
Deb

Try going to http://www.artmetal.com/ the into the sculpture area
(also try the jewelry area) and do a search for patinas. If you
still need more info, post to a Tech Talk area or sign up and post to
the list.

Get “The Coloring, Bronzing and Patination of Metals” by Richard
Hughes and Michael Rowe. Great book.

Hope this helps.

John Dach
MidLife Crisis Enterprises
Cynthia Thomas Designs
Cynthia’s sculptures are at: http://www.mlce.net

#5

Some years ago Charles Lewton-Brain showed me and some others a
patina on copper that is blue-green and very quick to achieve. He
dabbled a paste of salt and water on the article, which had been
thouroughly wetted with water. Then he placed it on top of a small
jar which was up-ended in the middle of a shallow glass dish filled
with ammonia. Then he covered the whole thing with an up-ended
container, perhaps it was a plastic pail. Within a fairly short
period, couple hours or so, a beautiful blue-green patina appeared.
He had a few other simple patinas too. Get his “Patinas for Small
Studios”.

David L. Huffman

#6

“the green patina refers to ammonium chloride and says another name
for it is sal ammoniac. where should i look for this ingredient?”

Jean, If I’m not mistaken, sal ammoniac should be able to be found in
a hardware store in the soldering section. If not, then definitely
where one would buy stained glass supplies.

The sal ammoniac comes in a hard white bar form and is used to clean
the dirty build up from the tip of a hot soldering iron. It works
great.

Karla from Sunny So. Cal

#7

mary, you were on the money with the sal ammoniac. i found it at a
small, neighborhood hardware store that has a little of everything.
it was in the soldering supplies. the young clerk had never heard of
it. his eyes lit up when he found a cake of it in an old, cardboard
box. he said that he had learned something today (along with me).

by the way, as i was looking through all of their stuff, i found a
treatment for “shuffleboard courts and dance floors.” the metal lid
of the can was rusted, so that gives me an idea about how long it has
been in the store.

thank you,

jean adkins

#8 
    i'm interested in trying some of the nontoxic recipes for
creating patina on copper ... mentioned that a salt and water paste
would create a patina on copper.

G’day; you might have to wait a long time, for heating would help,
but I would suggest that salt moistened with vinegar and warmed would
be better.

   ...mentioned how  flux for lead-based solder created a blue-green
patina.

The usual flux for lead based solders contains zinc chloride. This
would probably create a blue/green colour - again if warmed. Not red
hot!. Virtually any patina provided by such chemical means would
certainly wear off in time. Why not just try whatever you think might
work, on a bit of scrap copper? after all, it is very cheap and easily
obtainable. Most of such chemicals require an acid to react with the
copper, and the most common ones seem to include the chloride ion - as
in sodium chloride (salt) and ammonium chloride. (Sal Ammoniac) -
but it must be clean, though not necessarily oxide free. What about
trying lemon juice and salt? Etc?

You mention ‘non toxic’. I would argue that there is no such thing -
everything can have a deleterious effect on humans; a synonym for
’toxic’ is really just ‘too much’ Simply don’t breathe it, or get it
on your hands, eyes, etc - whatever it is. After all rubber or plastic
gloves are cheap enough, and you don’t have to taste or breathe
everything you use. Common sense must prevail.

I personally would not recommend wearing copper next one’s skin; the
body exudes a variety of mildly acid oils and slightly corrosive sweat
(that contains salt for one thing) to react with copper, and the
results can be re-absorbed and might not be good over time. But
don’t let a miserable old ******* like me spoil your fun. Cheers,

	John Burgess;   @John_Burgess2 of Mapua Nelson NZ
#9

john burgess, thanks for the copper patina advice.

it reminds me: i think you should write “elementary chemistry for
jewelers.” it could be a small book or brochure, or a series of
articles for a periodical-- like the soldering series sara sanford has
been doing for lapidary journal. i bet you have already done a lot of
the writing in the messages you have sent in orchid.

jean adkins
columbus, ohio

#10

Karla, If you can’t find sal ammoniac (Ammonium Chloride) you can
make a solution of it as follows: To 4 cups of water, add 1 cup of
household ammonia. Then add 1/2 cup of muriatic acid. The two react to
form Ammonium Chloride. This will leave a little excess ammonia which
is desirable for patination. Caveats: 1.0 Do this outside or someplace
with VERY GOOD ventilation. 2.0 Add the muriatic acid VERY SLOWLY to
the ammonia solution, stirring constantly. When you bring the two
solutions near each other you will notice a dense "smoke. This is
Ammonium Chloride forming in the air. Get upwind of it.
Regards…Bob Williams Karla