http://www.techradar.com/us/news/computing-components/processors/how-sand-is-transformed-into-silicon-chips-599785 http://www.techradar.com/us/news/computing-co

http://www.techradar.com/us/news/computing-components/processors/how-sand-is-transformed-into-silicon-chips-599785 http://www.techradar.com/us/news/computing-components/proces... http://www.cam.ac.uk/research/features/solar-grade-silicon-at-low-cost/ http://www.cam.ac.uk/research/features/solar-grade-silicon-a... That's 30 seconds of Googling. I can't vouch for how accurate they are.