The reason they were categorized different is they didn't have anything in common. Well this is what i came with. They all are made up of electron, proton and neutrons.
they are ALL called malleable.
Well see people take dumps in the ocean then the dumps start on fire which then turn into ash and sink to the bottom forming sediment.
Ocean sediments are deposits of materials(organic or in-organic) at the substractum of the ocean.
iron steel aliminum copper tin these are all common metals - hope that helps