Metcore Alloys are proud to present Corten Weathering Steel, the new material owning the most extraordinary property: it withstands the harsh forces of weather and gives an unmatchable aesthetic touch to any project. Corten Weathering Steel, sometimes also referred to as weathered steel, is a high-strength low-alloy steel used basically for structural applications. It bears a visible stable rust-like appearance after it has been exposed to weather.