I wrote this book because I could not find one like it. I am one of a vanishing breed in North America — professors who teach extractive metallurgy. Extractive metallurgy used to be defined as the winning of metals or alloys from naturally occurring ores, but over the past half-century this has changed. Increasingly, the ore body is now found on the ground, rather than in it. The majority o( iron and steel produced in North America is now obtained from recycled material, as are 40% of the copper. 80% of the lead — and more than 50% of the aluminum. Asa result, extractive metallurgy instruction now includes significant exposure to recycling technology and the unique processes used to recover metal from this strange type of ''ore.''