The Patina Process |
|||||||||||||||||||
| Patina refers to the change in an object's
surface resulting from natural aging. In bronze sculpture, patina refers
to the surface of the bronze itself and is often altered by the sculptor
with acid and/ or the application of heat and chemicals to achieve
various colors. Artfully applied, patina highlights the modeling of the bronze, enhancing its beauty and value. It also serves to amplify contours. The patina work on Steven's sculptures are done by Bill Lowery of the Best in Bronze Foundry, Kalispel, Montana |
|||||||||||||||||||
| After the bronze is removed from the mold, it is cleaned and then blasted with glass beads to prepare it for the patina process. |  |
||||||||||||||||||
 |
Next, the bronze is dipped in potassium sulfide, commonly called "liver" because of the color. This creates a uniform patina of the color often associated with "bronze" sculptures. | ||||||||||||||||||
| The next step is to apply a pastel base using a "secret" transparent white formula with a nitric acid base and the heat of a propane torch. |  |
||||||||||||||||||
| The process continues with the application of various chemicals to create the different colors. These include ferric nitrate, to create yellow to iron red. The color is based upon the temperature of the metal and the layers of chemicals in the base. Cupric nitrate results in greens, the natural patina of copper exposed to the elements. The artist speeds up natures process with heat and acid. Silver nitrate is used to create silver and grays. Cobalt nitrate yields black to dark blue black. Blue m-20 gives a blue black "gun blue". Bismuth nitrate yields blue whites. | |||||||||||||||||||
 |
 |
 |
|||||||||||||||||
 |
 |
 |
|||||||||||||||||
 |
 |
 |
|||||||||||||||||
 |
 |
 |
|||||||||||||||||
 |
 |
 |
|||||||||||||||||
 |
|||||||||||||||||||
|
|||||||||||||||||||
