Before revision: Steel The 630 foot (192 m) high, stainless-clad (type 304) Gateway Arch in Saint Louis, Missouri Steel is an iron alloy with controlled level of carbon (between 0.0 and 1.7% carbon).
After revision: Steel The 630-foot (192 m) high, stainless-clad (type 304) Gateway Arch in Saint Louis, Missouri Steel is an iron alloy with controlled level of carbon (between 0.0 and 1.7% carbon).