We may receive a commission when you use our affiliate links. However, this does not impact our recommendations.
Top to bottom:
A Paint color: black; foil: silver
B Method A was oxidized using Sulfurated Potash
C Paint color: red; foil: copper placed onto top of netting then removed. Gold fold added to create an additional effect when oxidized
D Method C was oxidized with Barium Sulfide
By combining paint, metal leaf, and some chemical reactions, you can create interesting effects on a variety of surfaces.
Creating a Patina finish can transform any object into a work of art. I have used these methods for over 3 decades with excellent results. My art pieces have sold for thousands of dollars and won awards using the very same techniques that I’m sharing with you here.
Surface Preparation
I begin with surface preparation. Sealing the surface, be it wood, plastic, metal, ceramic, or even vegetables like gourds, can be easily done with shellac. Sometimes I mix my own, but I find it easier to purchase it already mixed.
My work involves multiple layers and color is a big part of the process. I like the Zinsser BIN primer which is alcohol-based and dries fast. The white color gives a perfect background for the other layers of color.
I like to spray finishes, when possible, for speed and lack of brush marks. Shellac bonds well to just about any surface. I apply a couple of coats and sand it smooth between coats with 220 grit sandpaper.
1 When working with patinas, I like to make up sample boards to test out colors and chemical reactions.
Color & Size Preparation
The next step is to apply some color. I like to use Japan paints because of their rich colors. I thin them with Naphtha, although paint thinner works too. It’s just slower drying. I pour it through a paint filter and spray it on. An inexpensive spray gun works fine as long as you add enough solvent to make it flow.
2 Run the size through a fine-mesh paint filter to remove any particulates.
The Japan paints are still porous when dry, so they need to be sealed before applying the oil-based size, which is also known as leaf adhesive. To do so, I apply a layer of oil-based size to seal the surface. I like to pour it through a paint filter first. This will remove any dried flex of resin or dust or anything else that gets in there. Lastly, I use a soft square-edge, inexpensive synthetic brush to apply the size.
Once the size has dried overnight, I sand it smooth with 320 grit sandpaper or higher.
3 After sealing the surface with size and sanding it smooth, brush a coat on, making sure it’s smooth.
Adding Metal Leaf
Now that the surface has been sealed, I can brush on another coat of size, which will act as the glue that bonds the metal leaf. As I mentioned, I’m using an oil-based quick dry size which tacks up in about an hour and stays open for about an hour or two (this is the working time you have to apply the metal leaf). It’s important to wait until the surface has a dry tack, similar to masking tape. You can lightly touch your knuckle to the surface to see if it feels like masking tape. If it’s too wet, it will go right through the thin metal and ruin it. If it’s too dry, the metal leaf will not bond.
Method A
I like to have some of the background color show through, so I intentionally tear the silver leaf as I’m laying it down to create cracks in the surface much like marble or granite. Once the entire surface is covered, I place a piece of wax paper over it and hold it still with one hand while I use my other hand to lightly rub the metal into the size for a good bond.
4 Lay the leaf onto the surface.
5 I prefer to allow it to crack in some areas.
6 A soft brush can be used to move around and “stick” down the leaf in targeted areas.
7 Cover the surface with a layer of waxed paper and rub the surface down to smooth it out.
Method B
Sometimes I like to use a resist material such as the vegetable net bags that you see in photos 8-10. They are made of plastic so they will temporarily stick to the varnish (a.k.a size), but they will also release. This allows me to place the metal leaf on top and then tamp down with a soft brush, pushing it through the netting.
8 Using plastic netting from an onion bag has an organic texture that makes an interesting pattern.
9 Use a paintbrush to stipple and dab the leaf through the netting onto the size.
11 Carefully peel up the netting from the surface. The netting will remove leaf with it and offer a pattern on the surface.
12 Using different leaf types, such as 22k gold, will cause a variety of colors across the surface once the chemicals have had a chance to react.
The end result is a sort of organic flowing surface with some negative spaces that allows the background Japan paints to show through.
Once I clean away the loose pieces of metal leaf (called skewings), I can add more metal because the size is still tacky. In photo 12, I’ve added a little bit of 22 karat genuine gold leaf for some accents and highlights.
Let the metal leaf and size dry overnight. The next day I come back and buff it smooth with a soft organic cotton ball. I do warn you that the synthetic cotton could have course fibers in it that can potentially scratch the metal.
Oxidize with Potash Sulfurated
Some people prefer to leave the metal just as it is. My preference is to oxidize the metal and create various color.
My favorite chemical for silver is Potash Sulfurated, which is also referred to as Liver of Sulfur. This chemical can create a rich blue color on the silver as well as golds and reddish tones. It works especially well if you can apply this outside in the sun. At first you will see the metal turn a golden color, then it progresses into a reddish color which will darken into a beautiful blue color.
13 Sulfurated Potash appears as soft pieces of rock.
14 Once you dissolve them in water, it will have a yellow color with a rotten egg smell.
When you purchase Potash Sulfurated or Sulfurated Potash, you’ll find that it looks like a series of small, yellow grayish rocks. You can break them up with a hammer after placing some in a plastic bag. Then they will readily dissolve in warm water.
Begin by pouring a 1/2 cup of water into a plastic or glass container and then add a 1/4 teaspoon of the chemical to the water. The general rule of chemistry is to always add the dry chemical to the water. Never put the dry chemical in the container first and then add water because it could cause a reaction. I have to say that over the last several decades, there have been times when I have accidentally reversed this, but I’ve never had any problems with it. That’s because all of the chemical that I use are really mild acids.
Once you’ve prepared the chemical mixture, you’re ready to introduce the acids to the metals. The lesson to be learned with patinas is that the vehicle you use to introduce the acids to the metals will determine the pattern generated. In other words, if you put the chemical solution in a spray bottle and spray it on, you’ll get a spray pattern. If you dip a paintbrush in the solution and brush it on, you’ll see the pattern of the paintbrush.
I like to create an organic, random looking surface, similar to what you see in rocks or marble. In order to achieve this look, I’ve tried sawdust, pieces of cloth, fuming, and other creative ideas but one of my favorite methods is to use dry cheese cloth and tissue paper.
15 Layer the surface with a dry piece of cheese cloth, stretching it out to a random pattern.
16 Cover the piece with a thin piece of tissue paper that’s been wrinkled.
17 You can use a spray bottle of water to dampen areas of the tissue paper, which will cause the chemicals to bleed and blend.
18 Flatten down the surface with wax paper and a roller.
19 Gently dab on the chemicals, trying to be random with your pattern.
I set up all my materials outside, so I am prepped and ready to go. I begin with a piece of dry cheese cloth and pull on it to create a random pattern. Then lay that down on top of the surface followed by a piece of twisted up tissue paper. The tissue paper will create wrinkles. Next, I’ll use an acid brush, which is essentially a disposable brush with a metal handle and begin to brush the chemicals on top of the tissue paper. Since the chemicals are water soluble, they will begin to spread through the tissue paper and down into the cheesecloth by capillary action. Keep an eye on it and once you start to see the beginning of the blue colors, wait for a few minutes, and then remove the tissue paper and cheesecloth. Be aware that the colors will continue to progress even after you remove the tissue paper. Once you get to this step, it’s important to take it out of the sun and put it inside to allow the surface to dry. I like to let it dry overnight before sealing it.
20 After applying the chemical, let the piece sit in the daylight.
21 Keep an eye on the surface. You’ll see the Potash starting to react with the silver leaf.
22 When you feel as though the surface has reached the look that you want, remove the cheese cloth and tissue paper and bring the piece inside and out of the sun to stop the reaction.
Oxidize with Barium Sulfide
Another option is barium sulfide, which works really well on copper. The proportions are the same, 1/4 teaspoon of chemical to 1/2 cup of warm water. Be aware that the barium sulfide is a heavy metal, so you want to make sure to wear gloves and not get it on your skin! Copper is the most reactive of all of the metal leafs.
23 Barium Sulfide is a heavy metal, so make sure to wear gloves and avoid skin contact.
24 Dissolve it in water, and make sure not to splash it as you’re stirring it.
In this case, I crinkle up a piece of tissue paper and lay that down. Then take the liquid chemicals and brush it on the top. The reaction begins right away. You will see a dark purplish color and other random color in between. This should only take about five or ten minutes. At this point, remove the tissue paper. You can even blot it dry with a piece of tissue paper if desired. Like the Potash Sulfurated, be sure to bring it inside and let it dry overnight. The chemical reactions with barium sulfide will continue until the surface is completely dry so that’s why I like to let it continue to dry overnight.
25 Once again, spray down the tissue paper with water to bring it down to the surface.
26 Dab the Barium Sulfide mixture over the surface in a random pattern.
27 The reaction with the copper makes it appear aged and worn by time.
Sealing the Completed Piece
The next day, I’ll seal it in order to protect the surface. I like to use lacquer because it diminishes the colors the least. Even a thin light coat of lacquer will protect the surface from further oxidation. I do want to put it out there that the adhesive (the size) that I use is oil-based and the solvent in the lacquer can react with the oil-based size if you size it on too thick or too heavy. Therefore it is best to spray a thin light coat and give it plenty of hours to dry.
Once the first coat has cured, you can apply subsequent coats and you could even build it up to a guitar-like mirror finish if you want.
Here are some supplies and tools we find essential in our everyday work around the shop. We may receive a commission from sales referred by our links; however, we have carefully selected these products for their usefulness and quality.
