Crystal Growth by Vapor Diffusion
      Substances that are very soluble in one solvent and insoluble in a second solvent may be good candidates for crystal growth by vapor diffusion, two solvent evaporation or liquid diffusion. The two solvents must be miscible (soluble in each other in all proportions). For vapor diffusion, the poor solvent should be more volatile than the good solvent.
      Suggestions:
      - Put about 5 mL of a saturated solution in a 10 mL beaker. Place the beaker in a jar that contains about 15 mL of the more volatile, but poorer solvent. Put the lid on the jar and allow the solvents to reach equilibrium. - The liner of the lid to the jar should not react with the solvents. Lids with Teflon liners work well. - Some possible "good solvent/poor solvent" pairs are: water/ethanol, chloroform/ether, acetone/pentane.