The seafloor has some valuable minerals. Manganese nodules containing manganese, iron, copper, nickel, phosphate, and cobalt may be as small as a pea or as large as a basketball. Estimates are that there may be as much as 500 billion tons of nodules on the seafloor. The minerals in manganese nodules have many uses in the industrial world, but currently they are not being mined.

Why do you think these seafloor resources are not being mined? (Please write a complete sentence or two)

giving 50 points!