Quartz when heat and pressure are apllied to it

If you melt and cool silicon dioxide under very special conditions 
in the laboratory we can grow a single crystalline form of 
silicon dioxide that we call quartz. In quartz crystals all of 
the molecules are aligned and bonded together in a regular three 
dimensional tetrahedral structure forming a very hard, transparent 
material with special electronic properties. 

Solubility would be your answer.