Liver of sulfur

It is sold as a yellow brittle solid (a "lump" which must be mixed with water before use) as well as a pre-mixed liquid and a gel form.

Liver of sulfur that is kept dry, sealed from air, out of the light, and in a freezer will last many times longer than that kept in any other condition.

As it ages and is exposed to air, its potency decreases, it will turn lighter yellow and finally white, at which point its reactivity is negligible.

When treating silver, the solution must be hot, though if the bath is brought to its boiling point the liver of sulfur will quickly decompose and become ineffective.

Also, if the concentration of the solution is too strong, the oxidation process will proceed too quickly and the layer of patina thus created will tend to flake away.