Crystallization

Throughout the chemical process industries, formation of crystals is an important route to products of high purity. Click here to find out why slow forming crystals are so pure. The ultra pure silicon wafers for the electronics industry are made by repeated crystallization. As a crystal forms, the ions or molecules that fit exactly into the crystal lattice are preferred while the incorrect species are excluded. Often very pure crytals can form in quite impure solutions. Of course, when the mother liquor (the residual solution) adheres to the crystals, purity suffers. This is why good washing or removal of liquid from the crystals is critical.
  • Rapid precipitation tends to make impure crystals.
  • Look at some typical crystals of the mineral aquamarine with high purity:

  • Single crystal
  • Translucent green crystal
  • Translucent green crystal
    Continue
  • 26-July-95