New Crop Can Mine Nickel at a Low Cost

Mining for nickel now requires little more than a green thumb, thanks to a patented process created by the Agricultural Research Service and Viridian Resources, L.L.C., of Houston, Texas. Metal-loving plants can extract nickel and other metals from the earth without machinery.

ARS and Viridian partnered with the University of Maryland, Oregon State University and the United Kingdom’s University of Sheffield to show that phytomining--the use of plants to extract useful amounts of metal from soil--is commercially feasible. Utilizing certain plant species that accumulate nickel from contaminated soils, scientists developed an environmentally friendly alternative to traditional mining techniques.

ARS agronomist Rufus Chaney, working with Scott Angle (Maryland), Alan J.M. Baker (Sheffield), Yin Li (Viridian), and Richard Roseberg (OSU), targeted a number of plant species that hyperaccumulate, or recover unusually high amounts of metals through their roots. By evaluating several hundred strains of hyperaccumulating plants for favorable genetic characteristics, the team developed the first commercial crop capable of hyperaccumulating nickel, cobalt and other metals. This hay like crop is burned after harvest to create an energy byproduct, and the ash is a lucrative source of metal.

Phytomining creates a win-win scenario: the inexpensive cleansing of contaminated soil and the production of a valuable cash crop. Phytomining on contaminated soils is more lucrative than growing traditional crops on the same land. Harvests from low-grade pastures or forests grown on such land would fetch about $50 to $100 per hectare per year. But a phytomining crop growing on the same land would produce an annual 400 kilograms of nickel per hectare worth more than $2,000 even at today’s depressed market price for nickel. After selling the byproduct energy, the annual per-hectare value of a phytomining crop exceeds $3,000.

Additionally, the crop can tap the vast mineral deposits in the United States and other countries that are unavailable through today’s conventional mining techniques.

ARS is the U.S. Department of Agriculture's chief scientific research agency.