Grow Calcium Chloride Crystals

It's easy to grow calcium chloride crystals. The crystals are thin, six-sided needles that catch the light so that they seem to glow from within.

Materials

• calcium chloride (CaCl₂)
• water (H₂O)

Although you may not know it, you probably have calcium chloride in your home. This salt is used in moisture control products, such as DampRid, and in salt to remove ice from sidewalks. If you use road salt, check the label to make sure it's calcium chloride and not another chemical. You can also order calcium chloride online.

Growing Crystals

The procedure for growing calcium chloride crystals is essentially the same as growing table salt crystals or those of any salt. 

1. Heat water to a full, rolling boil. The solubility of any salt is highly dependent on temperature.
2. Stir in calcium chloride until it stops dissolving. If you like, you can filter the solution into a new container, discarding any remaining solids.
3. Place the container with the solution in a place where it won't be disturbed. Let the crystals grow.

Tips

• Ordinarily, you can remove crystals and preserve them, but calcium chloride is so hygroscopic, taking the crystals out and leaving them in the open air will lead to degradation within hours. It's best to appreciate these crystals in their solution.
• Calcium chloride crystals are naturally colorless. You can try to color the crystals by adding food coloring to the crystal growing solution.
• One easy way to grow these crystals is simply to leave a container of DampRid hanging in your home or vehicle. Eventually, the conditions will become right for crystal formation.