The most common materials which are recycled are paper and glass. Some plastics, metals and textiles can be recycled as (1) ... . In theory recycling seems obvious: however, in practice it is not always cost-effective. Often the cost of collection and transportation is greater (2) ... the cost of the energy saved. It also means that (3) ... are fewer jobs available in industries (4) ... as mining, as demand for raw materials is lower.