Turning Silver and Copper Metals Black: Some Oxidizing Techniques
(Use bare wire, if you intend to oxidize it; this means it has no protective lacquer finish on it to prevent it from tarnishing)
1. USING LIVER OF SULFUR
Step 1 Preferably work outside when using Liver of Sulfur (LOS). Make sure you wear gloves and designate glass or ceramic containers that will be used solely for this purpose.
Step 2 Clean the silver before you begin. Any polishing residues, wax or fingerprints could affect the consistency of the oxidation. Hot soapy water and an old toothbrush work well.
Step 3 Make a neutralizing bath. You will use this later to neutralize the silver once you have finished oxidizing.
Step 4 To make the neutralizing bath: Using one Mason jar, mix two teaspoons of baking soda in one cup of cold water.
Step 5 Stir solution until the baking soda is dissolved. Set aside for later.
Step 6 Prepare your workstation. You need two mason jars with one cup of hot water in the LOS solution, the neutralizing bath you just made, Liver of Sulfur, the silver you wish to oxidize, a pair of gloves, a plastic spoon and some paper towels. (Hot water (not boiling): 30 seconds in microwave) (Use glass jars, not plastic)
In the one with the piece you wish to oxidize, if you use hot water, oxidation will occur very quickly. If you use room temperature or even ice water, the oxidation will take longer to occur. With silver, this will give you an opportunity to control what color tone the final piece will have. But with copper, the metal darkens extremely fast.
Step 7 Drop the silver into the water (hot, room temp or cold) of one Mason jar.
Step 8 In the other Mason jar add 1 pea sized lump of LOS to the hot water.
The hotter the solution, the faster the oxidation. Alternative: Room temperature LOS solution, and put silver in ice-cold water. A greater temperature difference slows patina process, and can get more variation in colors with blues and golds, not just blacks.