Solanum™ Steel

Weathering Steel, Preweathered

Solanum™ is our pre oxidized weathering steel Patina that provides artists, architects and designers with a range of resonant tones on an enduring surface. We produce this finish by accelerating the natural weathering process and stabilizing the result, Solanum™ Steel.

In the early 1980's, Zahner coined "weathering steel" to describe the surface of Cor-Ten, a registered trademark owned by US Steel, and known for its enduring qualities as compared with mild steel.

Zahner has more than 40 years of experience and over a hundred projects successfully installed using weathering and pre-weathered steel surfaces for architecture and art. Our facility is clad in weathering steel.  There are no companies with as much experience and expertise in the use of weathering steel in the world.

The Science of Steel Begins at Our Source

We work with the mill source to ensure that the raw steel ingot is derived from specific alloying components, base raw material is cast to exacting specifications. Next, we work with a rolling mill that understands the finesse required when working with bare weathering steel. They are careful to avoid scratching. If you don’t influence the base metal sources they will treat the material like basic steel: it will be heavily oiled, scratched, and scarred. These contaminants will show in the final product as streaks, rings, and discolorations in the finished surface

We inspect each and every plate surface. Each surface of the bare Solanum™ is cleaned and prepared to eliminate oxides, greases, and oils. If this step is not carefully followed the finish will not hold up. Once properly prepared, we force the surface to an initial ferric oxide. This finish is slightly orange in color and is characterized by a crusty texture.

The Guggenheim Museum in Las Vegas.

Orange patina is not as permanent as dark patina. A finish with yellow and orange will rub off if not properly finished, and it will continue to darken, bleed, and stain adjoining surfaces. Orange is soluble.

Within our facility, we allow this orange-toned oxide to grow to a point, and then remove most of it from the surface. The surface is then exposed to a proprietary solution and specific atmospheric conditions to develop a hydrated oxide form of ferrous oxide or ferrous hydroxide.

This is insoluble.

We cultivate the growth of the hydrated oxide form until it reaches a certain point. Then we arrest it with another proprietary solution that inhibits and slows oxidation to a standstill. The material is in its final stage of development.

For interior application and all areas of high pedestrian interface, we recommend sealing the surface using our proprietary methods and products.

This is Solanum™ Steel.

Our Steel Stains Less

A sealed Solanum™ finish does not come off when rubbed, nor does it readily come off and stain adjoining surfaces over time. Weathering Steel is known for staining adjacent surfaces with iron oxide as the material continues to age. Our preweathering process reduces, and often eliminates, staining of surrounding surfaces.

Projects Using Solanum™ Steel

• Spaceport America Designed by Foster+Partners
• Guggenheim Hermitage Designed by Rem Koolhaus
• McCoy Federal Building Designed by Schwartz+Silver
• Trinity Audubon Center Designed by Antoine Predock

Contact us to learn more, or download our Solanum™ Booklet.