Ferrous Scrap - Ferrous metals include mild steel, carbon steel, stainless steel, cast iron, and wrought iron. These metals are primarily used for their tensile strength and durability, especially mild steel which helps hold up the tallest skyscrapers and the longest bridges in the world. You can also find ferrous metals in housing construction, industrial containers, large-scale piping, automobiles, rails for railroad and transportation, most of tools and hardware you use around the house, and the knives you cook with at home.

Due to the high amounts of carbon used when creating them, most ferrous metals and alloys are vulnerable to rust when exposed to the elements. While this isn’t true of wrought iron, which is so iron pure that it resists oxidization, or stainless steel, which is protected thanks to its high chromium content, it’s a good rule of thumb that if you see rust, it’s a ferrous metal.

Most ferrous metals also have magnetic properties, which makes them very useful in the creation of large motors and electrical appliances. The reason you can tack your child’s artwork to the refrigerator with that magnet with the local pizza place’s phone number on it? Ferrous metal.

Most importantly, ferrous metals make up the most recycled materials in the world. In 2008 alone, 1.3 billion tons of steel were produced, and 500 million tons of that was made from scrap materials.