Crystal Growth by Slow Evaporation of the Solvent
     Substances that are moderately soluble at room temperature, and which are either not much more soluble or are unstable at higher temperatures are good candidates for crystal growth by slow evaporation.
- Prepare a saturated solution, filter it, and place it in a beaker. Cover the beaker with foil or wax into which a few small holes have been punched. 2-3 pin-holes in parafilm over a 10 mL beaker works well, as long as the solvent does not dissolve the parafilm. Aluminum foil may be used if parafilm is a problem. - Check the solution each day. It is important to harvest the crystals before all of the solvent has evaporated.