Our Patinas

Dark Green is a somewhat tricky and highly variable multi-layer torch technique patina. It starts with a layer of blue-green, which is then covered with a layer of a transparent black patina—a solution of sulphurated potash (also known as liver of sulphur). By varying the strength of the potash solution, colors from a leaf green to black and brown streaks or mottling can be achieved. The lighter colors, which are more commonly aimed for, require great care not to burn the surface as the second layer is applied, as this patina is quite unforgiving, and black burned spots are unrecoverable short of starting over from scratch. With careful brushwork and control of heat and patina concentration, many widely varied effects can be obtained.

A happy accident with dark green led us to Black. It begins simply with a doubling of dark green; that is, a four-layer patina:

1. Blue-green
2. Potash black
3. Blue-green
4. Potash black.

At first this yields anything from a muddy dark, dark green to a matte black—neither very attractive. However, after it is allowed to cool and dry overnight and waxed, it can be buffed with a soft brass wire brush and brought up to a shine and richness which looks like polished stone.