Made of Corten steel, but processed in order to have a protective layer on the surface to make it weather-proof. The surface is originally greyish; due to the weather conditions it turns reddish-brown (resembles the colour of rusting), which becomes darker within time. DURABLE MATERIAL: This wood-burning outdoor fire pit is constructed from Corten steel with a rust-patina finish, making it durable and long-lasting. The unique finish is formed from its exposure to atmospheric conditions, and the rusty surface gives it an antique look. ELEVATED BASE: Equipped with a base that creates a sturdy foundation for the fire pit, ensuring stability and preventing the ground from overheating. DETACHABLE DESIGN: The upper and lower parts of this wood burning fire pit can be separated. To dispose of the ashes inside, simply move the upper bowl (Note: do not touch or move until completely cooled). SPACIOUS INTERIOR: Overall dimensions: 23.8" L x 23.8" W x 19.5" H, with an interior depth of 7", providing ample space for wood to burn longer. TIPS: To speed up the rusting of the Corten steel fire pit and make the surface more beautiful, spray evenly with water or salt water using a spray bottle or wipe with a cloth, then allow to dry naturally.