This handcrafted outdoor fire pit is constructed entirely of 11 gauge Cor-Ten steel. Commonly called "weathering steel" it will develop a beautifully brown layer of rust when exposed to the weather. The weathering rust actually performs as a protective coating providing greater resistance to corrosion compared to other steels. It will take 2-4 months for the steel to fully rust. The fire pit is designed for wood burning or using lava rock or decorative glass. Natural gas or propane gas models are also available. Approximately 25 lbs of glass will be needed (not included).