What is the critical angle for the interface between water and fused quartz?
No, you can buy quartz at almost any rock store for about $5.
lots of different grades of quartz, but no, they generally aren't that expensive for a chunk of the garden-variety clear stuff... you might want to check a pile of gravel, or a garden supply shop. Good luck!
Try your local New Age store...They'll have all different sorts of rocks priced between $1 and around $150 depending on size, quality and type of stone...
A piece of rough quartz about the size of a gumball is often only $1-2
