Is there enough gallium to light the world with GaN-based white LEDs?
Gallium nitride (GaN) is the semiconductor material of choice for solid-state lighting. GaN is part gallium (not a plentiful mineral) and part nitrogen (plentiful, in the atmosphere). Even though gallium is not plentiful, if white LEDs achieve the efficiencies envisioned in the 2002 OIDA Roadmap (see above), there is still enough gallium to light the world with LEDs. A rough estimate of the amount of gallium necessary to do so is 50 tons/year. Worldwide gallium production capacity in the year 2003 was about 200 tons/year, with actual production about 100 tons/year (see 2003 USGS Minerals Yearbook — Gallium). Hence, the additional use of gallium for white LED lighting could be easily accommodated by the current production capacity. In addition, gallium is available as a byproduct of bauxite refining, with known reserves of bauxite enabling the potential production of about 1.1 million tons of gallium (see 2003 USGS Gallium mineral commodity summary ). Thus, there is more than enough of
