Corten Steel, also known as weathering steel, is a special steel originally developed for bridge building and skyscraper construction due to its incredible strength. It develops a protective, striking rust appearance on exposure to the weather, creating warm rich textures not always associated with metal. Due to the chemical composition of Corten Steel, a very dense oxidisation layer is formed during the weathering process which protects the blue steel inside. If this protective barrier is compromised, it will simply form a new skin to protect itself. Corten Steel is extremely durable and has a far higher resistance to atmospheric corrosion than other steels, making it is ideal for use in fire-pits, planters and water features. Finish/Weathering When you first receive your Corten Steel products they will arrive in an un-weathered or partly weathered condition. Once placed outside the weathering process will begin. This can take some time; Corten Steel has a reactive patina period of between 3 and 9 months depending on location and climate. The patina or rust acts as a protective barrier – it will not penetrate or compromise the structural integrity of the material. The colouration of each item will vary as the weathering process takes place, eventually producing a rusty brown patina. Please note: Shipping calculated by Amazon is to mainland England & Wales only! Please contact us prior to purchase for costs to other locations.