What is COR-TEN Steel?

COR-TEN or weathering steel was developed in the 1930s by US Steel. It is a steel alloy that develops a rusted patina over time when exposed to the elements. The rusted patina is a protective oxide film comprised of copper, manganese, silicon, and nickel that provides corrosion resistance. 

It has been used in several famous buildings that showcase the beauty of this timeless yet modern material. Structures like the John Deere World Headquarters in Illinois; this building has been aging for the last 60 years as it was the first to use COR-TEN for an architecture project.


large building, red-rust color,

Longevity, unique appearance, and minimal maintenance make COR-TEN a key competitor. 

Originally developed to help build railroad coal wagons, the success of the COR-TEN led to it being prominent source material for outdoor art projects and construction in the 1960s. Rust prevention helps to eliminate the need for painting long-lasting outdoor pieces. The steel has now been used for decades by architects and artists alike to help provide a unique style to a design that can last up to 100 years. 


arena, nonsymmetrical oval, metal structure

Other stunning architectural projects that have used COR-TEN are...


    • Courtyard Theater (Stratford-upon-Avon, UK)
    • Design Museum (Holon, Israel)
    • Barclays Center Sports Arena (NY, USA)
    • Leeds Broadcasting Tower (Leeds, UK)
    • BIG’s twisting Marsk Tower (Wadden Sea National Park, Denmark)

A landscape option that surpasses competitors.

In recent years, the steel has made its way into the landscape world offering a sleek appearance that far surpasses any competitor. The orange-brown color in the patina that arises as the material ages comes from the 5% copper content in the alloy mixture. This bold color contrast well with the vibrant colors often found in landscapes. 

metal planter that has a red-brownish patina color containing vibrant, bright green grass. Installed next to sidewalk.

Edge Right has perfected the art of using the beautiful weathering steel for projects.

The term COR-TEN refers to the tensile strength and the corrosion resistance of the material. Edge Right uses variety A606-4 - thick enough to stay straight and not flex after installing. This provides a thick hard edge for that clean modern appearance that can't be found with over-the-counter, flimsy edging available at local retailers.

metal edging lining flower bed containing gravel filler, plants, and a small tree. Installed next to sidewalk.