• Cor-Ten Steel / Weathering Steel
• Stainless Steel
• Powder Coated Steel
• Blackened Steel
• Bronze

Weathering steel, best-known under the trademark Cor-Ten Steel, is a self finishing copper-nickel steel alloy. When exposed to the weather, instead of rusting, it's surface crystallizes forming a self-preserving and self-healing rich, dark, purple-brown, suede-like protective finish.
    
Stainless Steel is a high chromium content, rust resistant steel. The surface can be finished by sanding, graining, wire brushing, or polishing.
    
Powder Coating is a dry painting process.  Finely ground particles of pigment and resin are electro statically charged and sprayed onto the sculpture. The sculpture, being grounded, attracts the charged resin powder like a magnet. The sculpture is then placed in an 400 degree Fahrenheit oven, where the powder paint melts and flows into a beautiful and durable finish.
    
Blackened Steel is mild steel that is either hot rolled and has a black surface due to the manufacturing process, or steel that has been crystalline blackened.
    
Bronze used in sculpture is Silicon Bronze which is an alloy of copper and 2-3% silicon. A patinae may be applied by the chemical application of color accompanied by heat. The patinae is sealed under a wax coating and becomes a permanent part of the sculpture. Bronze may also be polished to a mirror finish.
  
The Bronze Casting Process