I need the approximate annual production of silicon crystals (boules) for a book chapter I am writing. Of the man-grown single crystals, silicon is first in quantity grown, and quartz (single crystal SiO2) is second. I know that about 3,000 tons of quartz crystals are grown annually. Does anyone here know how much silicon is grown? John R. Vig Army Research Lab. AMSRL-PS-ED Ft. Monmouth, NJ 07703-5601 JVig@ARL.mil or J.Vig@IEEE.org