Introduction

Abstract

Raw materials are needed for many purposes. For the making of a computer more than 30 metallic and non-metallic raw materials are needed. The production of a car requires more than 40 different raw materials, such as aluminium, iron and zinc for the car body, platinum or palladium for the catalyst and copper for the on-board electronics. Even a mobile phone contains 40 different raw materials, for example lithium, tantalum, cobalt and antimony.