Liver of Sulfur: Create Patina on Silver and Copper Jewelry
Whenever I teach hand-finishing jewelry workshops, I mix up a small solution of liver of sulfur. Inevitably, someone always asks, “What’s that stinky stuff?”
Liver of sulfur may be a little less than pleasant to your nose, but I can’t help but love it. To me, it’s the stuff that gives my silver jewelry designs so much character, which makes it invaluable in my mind. It’s a patina that sinks into the recesses of metal textures and shows nice contrast when I remove and polish it off the high areas. It’s what gives my silver jewelry soul. Do I like the smell of it? NO WAY! But do I like the results? ABSOLUTELY!
What is Liver of Sulfur?
Liver of sulfur (LOS) is a potassium sulfide. It brings out the textural details in metal jewelry and can make the pieces look antiqued. It is most commonly referred to as oxidizing, though that term is used erroneously, so just go with it; it’s got way too much stuff to do with chemistry to go into here. Most jewelers just call it oxidizing to keep things simple.
Liver of sulfur gives gorgeous results on silver and copper. I find it a bit more difficult to get a good patina on brass, and it has no effect on gold. Colors achieved with liver of sulfur can range from a golden yellow to dark gray or black. You control this with your application of the patina.
LOS comes in three forms: liquid, lump and gel. For years, I used the lump form, and it works fine, but I have found the gel form much easier to use with the same or even better results. My personal least favorite is the liquid form, and this is because when used in a classroom setting, students use way too much and it gets wasted. Plus, I don’t think it lasts as long or is effective as long as the other two forms. I have found that many people, even when using the lump form, make way too much solution. You only need the size of half of a green pea and about a quarter cup of water to make a good solution.
Liver of sulfur will deteriorate in sunlight, so if you make up a batch, keep it tightly covered and in a dark, cool place. Also, keep it away from tools and other acids.
Liver of Sulfur Prep
Before you jump in with your LOS solution, you’ll need to prep the metal for the application. First, the metal needs some “tooth.” A textured or lightly sanded finish works best. Liver of sulfur will work on a polished surface, but a surface finished with rouge to a high polish may take several applications and a lot of patience. A slight tooth, even with the 9- or 15-grit 3M Finishing Films, will work. The piece must be very clean, so I scrub it with a paste of pumice and water and then rinse it. Then, I don’t touch the part I wish to patina. Also, get a #5 soft, round, medium-priced watercolor brush. No need to mess up a real pricey brush, but neither do you want to leave brush hairs all over your jewelry. That’s a really unfashionable look. Make sure to use this brush only for your liver of sulfur treatments; you may even want to label it so it doesn’t accidentally get repurposed for another type of project. Also, use rubber gloves, and try not to breathe the “stinky stuff.” Safety glasses are a must. You don’t want this “stinky stuff” in your eyes. And, of course, keep away from food!
Liver of Sulfur Application Techniques
There are as many opinions of how to apply LOS as there are jewelry artists. Basically, it’s whatever works for you; it’s not rocket science, and there is no one correct application technique out there. Experiment for yourself to find out what you like. The following are some pointers to help you along the way.
Application depends on your desired finish. If you want a yellowish-colored silver, dissolve a tiny piece of LOS, either lump or gel, in a small glass container of cold water. As you apply the solution, it will go through stages of colors, from yellow to magenta to purple to dark blue. These changes can happen rapidly, so watch carefully. You may add a tiny bit of ammonia and a single drop of liquid Dawn detergent to sometimes get more vivid colors. The addition of an everyday iron tablet (yep, just like the vitamin) can give you a rich blue. When you get to the color you want, dip the piece immediately into cold water. That will help “set” the color.
Another application technique is to run hot water over the piece and then either dip it into a small glass container of LOS or use the paintbrush to paint it on where you want it. This will give you a gray to black finish.
Finishing After Applying Liver of Sulfur
Anyway, have fun, experiment and if you don’t like the results, liver of sulfur can be removed by placing the item in warm pickle for a few hours, by sanding, with pink pumice spiders or by heating with a torch. Then, you can start all over and try it again. Nothing teaches like experience! Whatever you do, have fun and be safe.
You can learn more from Lexi Erickson when you subscribe to Lapidary Journal Jewelry Artist, where she is a contributing editor and frequently writes about silver jewelry-making topics like soldering, hand-finishing jewelry, jewelry design and more. Her gorgeous silver jewelry is often featured in (and on the cover of!) the magazine.
Nikolas Lacquer: Finish1.com, or Allcraft Tools 800-645-7124.
Brass brushes: Allcraft Tools 800-645-7124