Some plants have been shown to accumulate heavy metals such as nickel, cobalt, cadmium, nickel and even gold, and studies are now being carried out to assess whether such plans could be used to extract metal from soil or ores that are sub economic for conventional mining. This area of study is celled ‘phytomining’ and will depend on the use of hyper accumulating plants. It is envisaged that hyper accumulating plants would be harvested from soil containing metal, the plant material burnt to give a small volume of plant ash (bio-ore) containing high concentrations of the target metal, and the final bio-ore smelted to yield metal. Such processes are not yes commercially viable. Phytomining could well appeal to conservation as an alternative to opencast mining of low-grade ores.