This is a mixture of potassium sulfides which has traditionally been used to darken or ‘antique’ silver and bronzes. This is usually called ‘oxidizing’ the surface though it has nothing to do with oxygen, what is really happening is that sulfur is reacting with the surface to produce the grays and blacks. Liver of Sulfur is the classic darkening patina for bronze, brass, and copper. Depending on the surface, the strength of the solution, and the application method, it will produce a golden brown to a burgundy black patina. It is most commonly used as a base patina to increase contrast between light and dark areas. Liver of Sulfur may be used hot or cold and must be water rinsed to stop the reaction. To create the patina, combine 1 tsp. with 1 pint of distilled water. The solution will deteriorate rapidly so it is recommended to only mix enough for a day or so. Unused chunks should be sealed and stored in a cool, dry, and dark location. This product is sold in a 2oz nugget.
For more information and help check out this awesome guide by Sculpt Nouveau *HERE*