The local library has this one, covers just about ALL art metals.
Depending on where you are, the chemicals may or may not be available,
they tend to be poisonous, explosive or both. Kind of spendy, check
the library FIRST. The problem with outdoor display is that the
chemical coloring tends to fade or change, a good coat of epoxy paint
might be better. Definitely better if it's steel, that eventually
changes to rust-orange no matter what the original color was.
Text of patinas.html follows. Book suggestions included.
"Patina" -- "A surface appearance of something grown beautiful esp.
with age or use."
Usually used in reference to copper, but also applicable to bronze,
steel, and other materials.
This is a very broad topic that depends greatly on the material being
treated, purity of the treatment, environment, and eye of the
beholder. There must be hundreds or thousands of ways to do this, and
some of them may be old wives' tales. I have no way to verify these!
For the most part these are quotes from postings. For the most part it
seems to rely on ammonia or other nitrogen compounds. Note that
ammonia can cause brass to stress fracture (e.g. don't clean firearm
cartridges with it!).
Cleaning the work is often stressed, and you can't usually get the
patina quickly. It takes time to simulate age!
"It is common practice to treat copper roofs with ammonium sulphate to
form the green color quickly; it is not exactly an oxide, and simple
weathering sometimes does not do the trick." (From: John Whitmore,
"Unless you want to waste a lot of time experimenting and then still
possibly not get a coating that will stay green, use a commercial
patina made for that purpose. We use it in stained glass work. I'm
sure it is available from anywhere that sells sculpture or
architectural supplies." (From: John De Armond, email@example.com).
"Currently I patinate the brass with "Verde-It" (a chloride acid) and
a blacking acid (selenium-based). Can anyone recommend other surface
treatments? I also shine with anti-oxidants "Nevr-Dull" and "Peek".
How long will these last? Can I do better? (I got tired of lacquering
wires...)" (From: Matt Brand, firstname.lastname@example.org)
[Electroplating a patina] "...the method consists of treating the
copper anodically in a solution of:
* magnesium sulphate 10 percent
* magnesium hydroxide 2 percent
* potassium bromate 2 percent
Solution is held at about 95 degrees C, current density of about 0.04
A/(dm squared) for fifteen minutes. Initially deposit is
CuS04.Cu(OH)2, but increases in basicity on exposure until the
composition of the patina is reached. This is from H. Silman, et. al.,
Protective and Decorative Coatings for Metals, Finishing
Publications..." (From: Rob Pauley, email@example.com).
"Here are a couple of green patinas to try:
* 1 Tbsp ammonium chloride (Sal ammoniac)
* 1 Tbsp salt
* 1 oz ammonia
* 1 qt. bottled or distilled water
Mix all in a plastic container that will be only for the patina mix
and not used for other things. Warm or hot water will help the solids
dissolve better. Spray the patina on the clean oil free copper and let
set for 2 or 3 hours to dry then repeat 3 or so more times until you
get what you want. You can also soak sawdust with the patina and pack
it around the copper piece and seal it in a plastic bag for a day or
3. I have never used this patina but I have seen it and it can be very
nice and smooth.
I have used the following patina a lot. In a glass container mix up
some nitric acid with water (1 part acid (reagent 75% pure) to 2 parts
water). Always add the acid to the water slowly. Add to that mix some
scraps of copper to dissolve in the acid until the acid no longer
dissolves the copper. Do this outside where no body will get into it
because it makes a deadly nitrous gas (not nitrous oxide). The
solution will be a very dark blue. You have just made cupric nitrate.
You can use a brush to apply the patina. Using a torch to accelerate
the drying can work well but be careful not to over heat because it
will turn black and crusty. The fumes are not good to breathe. This
patina can also be used like the first patina.
All patinas can, after they have set a few days, be waxed with paste
wax (car wax). I have a copper bowl with the second patina on it that
was waxed 3 years ago and it still looks good." (From: firstname.lastname@example.org)
"You can get cupric nitrate at chemical supply houses. It works vary
fast. I got a nice effect by dissolving about 2 tablespoons of the
cupric nitrate crystals in a plastic spray bottle (with about 1 quart
water). This was one of those sprayers that "Fantastic" cleaner comes
in. Pre-heating the copper alters the mottling and texture too.
Experiment on copper scraps with different strengths of solution and
amount of patina solution applied." (From: Daniel Wold,
"To colour Copper or Brass Green:
* Cupric nitrate Cu(NO3)2 40 grams
* Ammonium chloride NH4CL 40 grams
* Calcium chloride CaCl2, 2H2O 40 grams
Add distilled water to make 1 litre. Brush onto a clean surface. This
is from an old text book, I haven't tried this one, but others in the
book have worked well for me." (From: Steve Rayner,
"The most common is to wash with a mild solution of salammoniac
dissolved in water. Just brush (or preferably spray) it on & allow to
air dry. Repeat as necessary to achieve the desired results. If you
want an old roofers trick, and one that is much more effective I might
add, piss on it! It is still common practice for the roofing crew to
all pee in a communal bucket and pour it over the roof at the end of
each day to force a patina." (From: Gary Hubert,
"Well, one thing that works well for me is dormant spray, the
lime/sulfur kind. You can get it at your gardening supply store.
Produces some really colorful patinas depending on strength of
solution and how long you dip the metal." (From: email@example.com)
"Personally I use a solution of lime/sulfur dormant spray (very weak)
and let it sit for up to three months in solution. Or if your area has
hard water (lots of minerals) just drop it in the toilet tank and let
it sit until it looks good (this is a technique used by antiquities
forgers). A good solid patina takes time." (From: Carl Mork,
"NOTE: no patina is truly "tough". None of them can resist scratching.
All you can expect is that light surface contact won't 'knock' bits
off. You should plan to treat any patina with lacquer or plain wood
wax. Three methods come to mind:
* Get a plastic or glass sealable container. Put your copper in it
and cover it with a layer of salt. Put an open container of ammonia in
there. Seal the whole thing up, come back several hours later. This
gives a blue-green surface.
* Make up a solution of 2 cups water, 1 tablespoon salt, 1
tablespoon ammonium chloride. Put it in a spray bottle. Heat copper to
over the boiling point of water. Lightly spray the surface. The water
should immediately "sizzle" off. The color will take 5-15 minutes to
develop. May be repeated. This gives a more green than blue color.
* Get a container, fill with sawdust. Saturate the sawdust with
ammonia. Add lots of salt, mix well. Bury your copper in it. Come back
in an hour. This gives a very nice speckly blue&green surface. You can
control the speckle by how well it's all mixed together and how fine
the sawdust is."
(From: Mike Schechter, Mike firstname.lastname@example.org)
"From - 'Creative Gold and Silversmithing' by Sharr Choate Colouring
Copper Green "A patina is produced on the metal by brushing the
surface with a solution consisting of 1 gram each of copper nitrate,
ammonia chloride, calcium chloride, and 1 ounce of water. When the
colour is reached the article is set aside to dry. A patina can also
be produced by pouring a hot solution consisting of 1 1/2 grams of
copper nitrate and 6 ounces of water onto the metal and allowing it to
dry." (Quoted by email@example.com)
"The best 'cookbook' I have with patina formula is: METHODS FOR MODERN
SCULPTORS [see reference section, below] For pre-mixed patina and
coloring solutions in small amounts, the JAX brand handled by
Merritt's Antiques at 610-689-9541 are OK. They have several at
$7.50/pint. For my own work, I brew my own. Depending on what color or
effect I want, I use cupric nitrate, ammonium chloride and burned
oils, alone or in combination. For those who want to experiment with
small pieces, get some "gun bluing" at the local sporting goods store
and try different times and dilutions." (from: firstname.lastname@example.org)
"This [METHODS FOR MODERN SCULPTORS] is an OK book. Starting from
absolute scratch, I have been able to get the simplest recipes to
work. However, *there is no substitute for watching somebody do it*.
My advice to amateurs is, read the book first, then spy on your local
foundry, and see what the motion is like for heating an area evenly
with a torch, how to use a stipple brush, the way a cupric nitrate
solution should sizzle, how to keep drips away, what to do when you've
flamed the end of your brush and there are bits of charred bristle
everywhere. A thousand things that will never be in the book." (From:
"Regarding the hot oil patina: I preheat the metal, same as with the
aqueous solutions. Use the *minimum* amount of oil. Sometimes I cut it
with mineral spirits. Mostly, I stick with either Linseed or Tung
oils." (From: email@example.com)
"Copper (II) sulfide solution will react with the copper, but will
produce a greener tint. It does interesting things to other metals,
too. Copper sulfide comes as a solution, or translucent-blue pebbles
(like rock salt) or a fine blue powder. The latter two can be
dissolved in hot water to produce the solution." (From: Derek
"I believe you mean copper sulphate. Copper sulphide is a black,
insoluble material responsible for the color of some patinas along
with the oxide. I have used copper sulphate, and it fits the
description of the compound that you are describing. Have fun." (From:
"As for coloring metal - this is not my field, but I know a tiny bit
about it. In my opinion, it is best to color metal by changing the
color of the metal itself (rather than by painting it). There are
several books on the subject; "The Art of Patinas" and "The Coloring,
Bronzing and Patinization of Metals" [see reference section, below]
are two that come to mind. These processes involve oxidizing or
chemically reacting the surface of the metal to make it change color -
usually, this also protects the metal from further reaction to the
elements. If you wish to obtain some references on this subject, I can
recommend [Craft Books]. They have, at least, the book on Coloring,
Bronzing and Patination." (From: firstname.lastname@example.org)
"Clean and degrease the metal and dunk it in liquid flours of sulfur.
Brass doesn't put on a patina like bronze (brass being around 1/3
zinc). At least that's my experience." (From: email@example.com)
"A salt water or vinegar solution sprayed on the metal and sealed with
an open container of ammonia will produce a blue patina. I have
enclosed it in tupperware and garbage bags according to the size of
the piece. The fumes will react with the solution." (From:
"A permanent Patina for Copper (quoting from Henley's book): Green -
* Sodium chloride 37 parts
* Ammonia water 75 parts
* Ammonium chloride 37 parts
* Strong wine vinegar 5,000 parts
Mix and dissolve. Apply to object to be treated, with a camel's-hair
pencil. Repeat the operation until the desired shade of green is
reached. <end quote>
First off you may be wondering where to get these chemicals:
* Sodium chloride - This is table salt (NaCl)
* Ammonia water - This is what you buy when you buy liquid ammonia
cleaner (get the stuff without any other cleaning agents added).
* Ammonium chloride - This is a little tougher. This is sometimes
used in things like solder flux. However, it is also found in many of
those kids chemistry sets. Try a good hobby shop - they often carry
replacement chemicals for those sets (these are usually a little
pricey for what you get, but you don't need much).
* Strong wine vinegar - Well, you can by wine vinegar from the
grocery store (this is maybe 7% acetic acid). However, since acetic
acid is the chemical we're looking for, and it's also used in photo
fixing, you can find acetic acid in 28% and glacial(100%) at a good
photo shop. 28% is by far good enough.
Henley's says to use a camels hair brush, I've used one of those
small, triangular makeup sponges with success. Keep in mind that the
patina (verdigris) will appear as the solution dries on the copper
surface. Several applications will probably necessary to get the depth
of color you want. Heating the copper helps also, but isn't necessary.
Note! Don't soak the copper in the solution, it won't turn green and
the acetic acid will eventually start to eat away the copper!
Also, the copper sould be CLEAN when you do this. Steel wool and and
then wipe it with Hydrochloric acid (Muratic acid at your hardware
store - and be careful - rubber gloves, protect the eyes and get some
ventilation). I usually wipe off whatever remains of the HCL when I'm
done with a little distilled water." (From: Eric Kasten,
[Brown/black on bronze] "Liver of sulfur is, as obtained by me from
Bryant Labs, Potash Sulfurated (Lumps). I think that means "lumps of
sulfurated potash". It turns copper alloys brown, more or less
attractively varying with the exact alloy. By using a very
concentrated solution and/or several applications a dark brown can be
produced, but nothing I'd call "black". Adding some ammonium sulfide
(a _truly foul-smelling liquid also obtainable from Bryant) helps for
that, it gives a bluer-toned brown by itself. Either works ok cold and
very well hot." (From: firstname.lastname@example.org)
[It has been reported that "liver of sulfur" is potassium sulfide, or
a mixture of potassium sulfides. JK]
"Oppi Untracht has a few books out, one is called "Jewelry Concepts
and Technology", published by Doubleday. Another is "Metal Techniques
for Craftsmen (Persons)", also try Rio Grande Supply 800 443-6766,
they have great tech support and supplies." (From: Denise M. Maier,
[Rust finish on Ironwork} "Many metalworker/artists use muriatic acid
to get the finish you are after. Use with plenty of ventilation! Do
some background checking on how to mix acid with water (never pour
water into acid; do only vice-versa), what dilution to use, how to
neutralize surface after etching, how to handle, store, and dispose of
the acid. You can get some at a masonry-supplies store (it is used to
etch unwanted concrete grout off stone and brick). Be careful!" (From:
Laurence R Swain, email@example.com)
Steve Rayner ( snipped-for-privacy@freenet.Victoria.BC.CA) posted the following on
March 6 1996 as a way of bluing/blackening brass:
I just found this in an old Popular Mechanics book. The formula may be
of use to some of you.
* Sodium thiosulphate (Hypo).....1/2 pound
* Lead acetate...................2 Oz.
* Water..........................1 gallon (U.S.)
Heat to near boiling (200 F.), and immerse work piece in solution
suspended by a brass wire. Add more lead acetate to deepen the colour,
and speed up the reaction. I would suggest using a pyrex container, as
the hypo will react with iron directly blackening the container.
An article by Rand Esser, firstname.lastname@example.org, was
posted as part of a "newsletter" from ArtMetal. Rand has kindly
allowed me to include the information here, with the following notice:
Copyright 1994 Rand Esser. May be reproduced without permission by not
for profit groups for educational use only.
The introduction included:
Rand Esser, a Raleigh, North Carolina metalworker who specializes in
lamps and furniture, demonstrated the application of various patinas
on steel and brass. Rand uses chemicals to achieve different oxidized
surfaces on metal, often layering patinas on top of each other to
achieve unique and distinctive effects. The patinas are then sealed
with hot wax.
The article follows:
PATINAS ON STEEL
By Rand Esser
The patinas demonstrated at the March 12 meeting were copper sulfate
solution, Black Topaz, and Rusty Red.
I mix my own copper sulfate solution by mixing copper sulfate crystals
with water, a little at a time, until the water will no longer
dissolve the copper sulfate. Copper sulfate is available at Southern
Black Topaz and Rusty Red are sold by Sur-Fin Chemical Corporation.
Sur-Fin will send you a finish kit including seven six ounce bottles
of their finishes for $50 (they also sell patinas for other metals).
Larger sizes from one to fifty-gallons are available.
These finishes result in a variety of effects depending on strength of
the solution, reaction time, relative humidity, temperature, surface
texture, and type of top coating.
The Rusty Red and copper sulfate solution create similar effects. The
Rusty red seems to be a bit more red and the copper sulfate is a bit
more orange. I prefer the copper sulfate solution. It is more
beautiful and less expensive than the Rusty Red.
TIPS FOR PATINAS ON STEEL
The surface to be finished must be completely clean. Remove all scale
by sandblasting or wire brushing. Different surface textures will
create different results. Sand blasted surfaces tend to be more dull
and require a shorter reaction time. Wire brushed surfaces will be
shinier, but require a longer reaction time. I sandblast first to
remove the scale and then wire brush to create a shiny surface.
Remove all grease, oil, and, dirt with mineral spirits. Surface must
be white glove clean for best results. Different concentrations of the
finish solutions give different results. Sur-Fin recommends diluting
the Black Topaz 1:10 with water. I have used the Black Topaz at 1:5
with a very brown /black result. Different reaction times give
different results. I usually leave the solutions on for just a few
minutes. The Black Topaz ranges from a jet black with a short reaction
time to bluish, greenish, black with longer reaction times to
brown/black with very long reaction times. The Rusty Red and copper
sulfate solutions range from a light copper plating effect to light
rust to a dark crusty rust depending upon reaction time.
Some interesting effects can be created by using two or more finishes
on the same piece. The Rusty Red and copper sulfate solution will work
on top of the Black Topaz finish. The Black Topaz does not seem to
work on top of the others. I often begin with the Black Topaz and
drizzle, drip, or brush a pattern on specific areas of the surface,
leaving other areas bare. I then allow the Black Topaz solution to
react until it is dry. Then I come back and coat the entire piece with
the Black Topaz solution and quickly rinse the piece in water to stop
the reaction. The areas treated first will have a different tone than
the areas treated later. I then come back over the piece with the
Rusty Red and/or copper sulfate solution and brush, drip, drop or
drizzle it in specific areas to create coppery or rusty highlights.
The entire piece is then thoroughly rinsed with water to stop the
Once you have stopped the reaction by rinsing with water, allow the
piece to air dry or speed up the process by heating it with a torch.
At this point the piece is not very pretty. You will not know what the
piece will ultimately look like until you apply a top coat.
I usually heat the piece with a torch until it is barely hot and then
apply wax with a lint free cloth. I have heard that linseed oil also
works well. At this point the patina will reveal itself in its final
state. By applying more wax and rubbing I can usually remove some of
the more rusty spots revealing coppery areas. Additional coatings of
wax will create a shinier finish with more depth.
* These chemicals are poisonous. They will irritate your skin and
* Wear rubber gloves, goggles, protective clothing, and a
* Read the labels on these products and dispose of properly.
* Keep them away from your kids.
It takes time and experimentation to get good results with these
chemicals. Your finishes are likely to look different from mine due to
the many variables involved. I am continually experimenting with
different finishes on metals, steel in particular. I would like to
compile a data base of information on this subject to share with other
If you have information that you would like to share please let me
302 Glascock Street
Raleigh, North Carolina 27604
or send e-mail to: email@example.com
Vendor Addresses for Pre-Mixed Patinas:
Sur-Fin Chemical Corp. 1530 Spence St. Los Angeles, CA 90023 (213)
262-8108 Chemicals for mixing your own patinas. Bryant Laboratory 1101
Fifth St. Berkeley, CA 94710 800 367-3141 Supplier of Brass, Copper,
sheet, plate, bar, etc. Metal Supply Co. 4001 G St. Philadelphia, PA
[end of Rand's article]
On March 29, 1996, Charles Lewton-Brain ( firstname.lastname@example.org)
posted some advice on cleaning, and patinas on steel.
It is really impportant to have a clean surface for goodresults: This
may be Fantastick scrubbings, or more:
Cleaning Metal Surfaces, copyright Lewton-Brain 1985-91.
For all metal coloring and electroplating a clean metal surface is
essential. The cleaning process must remove mineral oils, organic oils
and greases as well as traces of chemicals on the surface. It must
remove oxidation which might interfere with the metal coloration or
plating adhesion and it should possible activate or roughen the metal
surface to better receive the treatment.
Cleaning may be accomplished using mechanical (abrasive), chemical
(heating, solvents, pickling with acids) and electrolytic
(electrocleaning, electrostripping) means. Examples of easily achieved
clean surfaces include sandblasted ones and ones scrubbed well twice
with rinsings using Fantastic. A pumice rub followed by scrubbing with
dishwashing liquid and ammonia on a toothbrush does pretty well.
Repeated scrubs with Fantastic work. Best of all is electrocleaning.
A simple procedure is:
* 1.0 Anneal and pickle in suitable acid.
* 1.1 Rinse 3-5 times in running water.
* 1.2 Dip into simmering ammonia and detergent solution and scrub
* 1.3 Rinse well 5 - 10 times.
NB: electrocleaning can be used after step 1.3. While steps 1.0-1.3
produce a quite clean surface by themselves if one is electrocleaning
it is not a bad idea to pre-clean using steps 1.0-1.3 so as to make
the electrocleaning solution last longer and lower it's work load in
cleaning the metal surface.
A much better and surer procedure is:
* 2.0 Remove oxides with pumice
* 2.1 Rinse well.
* 2.2 Electroclean for 1.5 - 2.5 minutes, object as cathode, then
reverse the polarity for a few seconds.
* 2.3 Rinse 3- 5 times in running water.
* 2.4 Dip in 1:10 sulfuric acid to neutralize the electrocleaning
solution and activate surface. (15 seconds or so).
* 2.5 Rinse 3 - 5 times in running water.
After cleaning, the metal should be placed in running or circulating
water (preferably distilled) to avoid oxidation until it is plated or
coloured. One can of course plate or colour immediately after
cleaning. In all cleaning methods the piece must either be wired to
suspend it in the solution or held with tweezers. It must afterwards
be very well rinsed to remove all traces of cleaning chemicals. Do not
touch the surface once it is free of grease.
Sand blasting may be substituted for steps 1.0 and 2.0 above, a sand
blasted surface is clean but can be damaged easily as well as being
matte in appearance.
Sample Electrocleaning solution:
* Sodium carbonate 50 grams Current density: 1-3A/dm2
* Trisodium phosphate 25 grams Polarity: 1 - 3 minutes Cathodic
* Sodium Hydroxide 25 grams 5 - 10 seconds Anodic
* Water 2000 ml
* Operating Temperature 60-70C
PATINA ON STEEL:
A method of patinating steel, copyright Lewton-Brain 1990
Warning: This procedure should be undertaken with appropriate
precautions; goggles, gloves, protective clothing, adequate
As part of a large scale patination project in which I patinated a
steel roof surface 24 by 48 feet on both sides I performed some 40
experiments to find out how to patinate the steel which was a
requirement for structural reasons. In doing so I also experimented
with paint, buying over $350.00 worth of spray paint, eventually
finding one single color which for all intents and purposes is green
patina. When placed in recesses and the high areas are rubbed off it
is indistinguishable from a cupric nitrate patina. It is a car paint:
GM 42, 1980 Chevrolet Medium Green. While this is ideal for smaller
surfaces my paint experiments did not produce the surface effects I
required on the large scale work. I reasoned that if I could plate the
steel with copper and then convert the copper to patina in a fume not
only would the job be easier but it would also be safer than dealing
with solvents or corrosive patination techniques (such as a cupric
nitrate patination) over large surface areas. I was dealing with 4 x 8
foot sheet steel to be equally patinated on both sides simultaneously.
Other types of objects might be easier to deal with. 'Tents' of
polyethylene plastic sheeting stapled to a framework of 'economy'
studs were built. The construction of such a tent requires that it be
sealed (draped onto the floor from the frame and then weighted down).
The object inside is positioned on supports of some kind so that it is
suspended off the floor in the air inside the tent. Then pans of
household ammonia are placed underneath the object. The fumes attack
copper or copper based alloy surfaces. Under normal conditions one can
activate a copper containing surface with a dilute salt solution to
speed up the procedure and obtain a blue patination but this proved
too corrosive for dealing with steel. The final procedure chosen was
1) The steel was cleaned well. Sandblasting would be ideal but was
impractical for the project. Solvents were also out for safety reasons
on such large surfaces without good ventilation. We ended up using
Fantastic cleaner. Two scrubbings with Fantastic on large sponges and
good rinsings in between and after were adequate most of the time. The
surfaces were then left damp with the rinse water. Only the edges were
handled to avoid contamination of the cleaned surfaces.
2) A contact plating solution for copper plating was prepared (see
below) and this was applied to the steel using paint rollers
(goggles/gloves!). Brushes work also but the paint roller is a bit
more gentle. Plating occurs instantly. Several passes may be made over
the same area, without pressing hard, which can remove the delicate
plating. The surface was then rinsed very well. If areas of the
plating lifted grease residues were the cause and a further local
Fantastic sponging and good rinsing sufficed to allow plating to take
place. After final rinsing the steel (held by the edges) was taken to
the tent. One moves fast to retain the surface moisture.
3) The steel was then placed in the tent and pans of ammonia enclosed
under it. The tent was sealed. The centers of the thin sheet sagged
causing pooling, therefore we built a wooden support with a single
nail pointing upwards to support the sheet. More stable objects would
not need support, though pooling may be factor to consider depending
upon the surface relief. The time required to convert the copper
plating was optimal at about 1-1 and a half hours.
4) The steel was removed and gently rinsed as scrubbing or hard
spraying can remove the delicate patina surface. It will be a mixture
of blues, greens and hints of brownish red where pooling has occurred
and the surface dried. In my case I chose to re-introduce pink spatter
marks to the surface by spattering droplets of the contact plating
solution onto the patina surface where they instantly went
pinkish-brown. The steel was then dried with fans and immediately
sealed using clear automobile enamel paint. I then went back with
stencils and gold spray paint to further modify the surface.
The steps in the procedure are then: Clean, rinse,plate, rinse, fume,
rinse, dry and seal.
The conversion process
The copper on the surface is attacked by ammonia liquid, not as much
by the fume which has a different chemical composition than the
liquid. The water dampened surface slowly takes in ammonia fumes where
they are converted to ammonia liquid in solution so that they can
attack the copper. The purpose of the pans of ammonia below the object
is to provide a constant vapor pressure which replenishes the ammonia
on the surface at a constant rate as it is used up in converting the
copper to patina. This system therefore ensures better overall
constant dilution control than beginning with ammonia on the surface.
Resists: Resists may be used to prevent plating or to prevent the
plating from being converted to patina by the fumes. Resists to
plating may be a greasy material (litho-crayon, oil) or thinned rubber
cement. Other resists require too much cleaning time and may need
solvents for removal. Resists to patination may be a protective spray
through stencils (Pam) or thinned rubber cement. Pattern control
through resists is easy.
Time: Time is a factor in all fumings. Experiment with various times
on sample pieces to have a palette of process marks (colors, tones,
effects) to choose from.
Pooling: Where pooling occurs variations in color will result. Pooling
can be encouraged and controlled by local application of greases
before or during patination and by the position and shape of the
object. Various liquid thicknesses cause surface variations.
Sealers: Sealers will each have a characteristic effect on the
surface. I recommend making a palette of various sealing options over
a patinated surface. Examples of sealers include waxes, oils,
lacquers, transparent acrylics, enamels, varnishes and so on. They
often have a tendency to darken the colors on the surface. I prefer
clear auto enamel or Spray-Lac number 1473 professional Finish Clear
Dead Flat lacquer. It is available from Star Chemical based in
Hinsdale Illinois, Deerfield Beach, Florida and Dallas Texas. It is an
industrial quality spray and requires good ventilation. It is very
unobtrusive on a surface. With any spray the surface chosen can be
glossy, like paint (in which case why not use paint?) or shortly after
spraying can be matted down with a cloth pad for better surface
Other Chemicals: I mentioned dilute salt solutions earlier. Many
chemicals will modify surfaces. (Remember never to mix bleach and
ammonia). Experimentation and sample making will offer the user
control choices. Suggestions for initial investigations include salt,
vinegar, baking soda and local heating. There are a number of
patination books available including one I sell on patinas for small
Contact Plating Solution Recipe All safety warnings apply. Always add
Acid to Water!! Goggles/Gloves!
250 grams copper sulfate (CuSO4) Technical grade chemicals for this
solution is fine. 42 cc sulfuric acid Distilled water to the 1000 ml
Put about 800cc water into plastic or glass container after marking
the 1000cc level on it. Add the copper sulfate and stir to dissolve.
Slowly pour a thin stream of acid into the swirling water. Heat is
evolved-be aware of this. Rinse the acid container with distilled
water and top up the mixture with it to the 1000 ml level. This
solution can also be used as an electroforming solution for growing
copper. Remember, acids are dangerous. A dust mask is suggested around
chemicals. Work cleanly. Copper salts are toxic and irritant and
should be handled with care. Dispose of properly.
Ron Young's books are very good for larger scale work. His
Contemporary Patination makes up for the poor safety attitude in the
Methods for Modern Sculptors book. The former is a working, useful
studio guide to patination unlike the monumental Colouring, Bronzing
and Patination of Metals put out in 1983 by Hughes and Rowe.
Ronald Young, Robert Fennell "Methods for Modern Sculptors"
Ronald Young "Contemporary Patination"
Source: Ronald Young
21 Redwood Drive
San Rafael, California
If ordering books through the mail New World Books is to be
recommended. They will obtain for one any book in print in North
America for 10-30% off the list price, including Jewelry Concepts and
Technology by Untracht for about $70.00. Their address is:
New World Books
2 Cains Road, PO Box 89
Suffern, New York, 10901, USA
Cheap Thrills in the Tool Shop, goldsmithing tricks book by Charles
Lewton-Brain. Also 'Patinas for Small Studios" 15.50 plus 3.00
Source: Brain Press, Box 1624, Ste M, Calgary, Alberta, T2P 1N3,
Canada (403) 263-3955, fax: (403) 283-9053, Email to
email@example.com (offers 10% discount to internet users)
[end of text by Charles Lewton-Brain]
* Henley's Formulas For Home and Workshop, Edited by Gardner D.
Hiscox, M.E. Avenel Books, New York (C) 1979. Originally published as
Henley's Twentieth Century Formulas Recipes and Processes, 1907;
Revised Edition 1927.
* METHODS FOR MODERN SCULPTORS, Ronald Young and Robert Fennell,
ISBN 0-9603744-0-X [available from Lindsay, catalog number 1257, for
* Contemporary Patination, by Ronald Young. Newer than METHODS FOR
MODERN SCULPTORS, with a better attitude towards safety.
* The Coloring, Bronzing and Patinization of Metals, by Richard
Hughes and Michael Rowe, published by Crafts Council, 1982, U.K.(ISBN
0 903798 60 3). I also have a reference to it as published by Thames
and Hudson, ISBN 0-500-01501-5. The book covers the patination of all
metals in depth, with Full colour plates to show all the different
effects you can achieve, these then relate to receipes in the book
which you can modify to your own particular needs.
* The Art of Patinas, By Michael Edge, Artesia Press,
PO Box 21, Springfield, Oregon 97477
$24.95 including shipping
* Finishing Handbook and Directory (this may be the same book as
* Metal Finishing - Guidebook and Directory, Metals and Plastics
Publications, Inc., One University Plaza, Hackensack, NJ 07601
* Protective and Decorative Coatings for Metals, H. Silman, et.
al., Finishing Publications, LTD., 1978 (ISBN 0 904477-03-7)
* Cheap Thrills in the Tool Shop, goldsmithing tricks book by
* Patinas for Small Studios, by Charles Lewton-Brain.
* Bryant Laboratory (chemicals, recipes)
* Craft Books
* Merritt's Antiques
* Jax Chemical
* Johnson Atelier Sculpture/Casting Supplies
* Lindsay Publications (METHODS FOR MODERN SCULPTORS)
* River Gems and Findings (formerly Rio Grande)
* Sur-Fin Chemical Corp.
* Brain Press
* New World Books
* stained-glass, and/or woodworking suppliers
The most powerful factors in the world are clear ideas
in the minds of energetic men of good will.
-- J. Arthur Thomson
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