I haven't looked into it yet but I wonder how much a quartz mine produces a year and compare that to PUREVAP'S feedstock requirements. I'm betting a single avg quartz mine only needs a 5000mt/y PUREVAP reactor to convert their annual mined quartz to a rich high purity silicon.
*Oprah jumps up at starts pointing to all the quartz mines* YOU GET A PUREVAP, YOU GET A PUREVAP, YOU GET A PUREVAP, PUREVAP REACTORS FOR ALL MINES!!!!