Grow Your Own Crystals!

Earth science is a common part of first grade curriculum, and kids usually adore it.  There’s always the thrill of messing with dirt … but there’s also the more delicate art of looking at rock formations and even crystalline “gems.”

Here is a real-life science experiment you can do to “grow” crystals in your home using simple, everyday ingredients.

What You Need:

• Shallow plastic tub or bowl
• Mixing bowl
• Piece of brick
• ¾ cup water
• ¾ cup bluing (from the grocery store or hardware)
• ¾ cup ammonia (also from grocery or hardware)
• Salt shaker with regular household salt

What You Do:

1. Make your crystal medium: In your mixing bowl, blend the water, bluing, and ammonia with a stick or spoon. Parents, beware: Make sure your child does not taste or touch this mixture!  Provide rubber gloves if needed.
2. Wet the brick with water from your tap, and place it in the bowl.  Pour about ½ cup of the bluing mixture over the brick—you’ll want it to cover the rough edges, where it will “stick.”  Then sprinkle the whole mixture surface with salt. 
3. Let the brick sit in a place where it will not be disturbed.  Check it out in about 24 hours—you’ll see small blue crystals starting to form!  “Feed” them by pouring another 1/3 cup or so of the bluing mixture on top of them.  Want to get fancy? You can even add some food coloring to make different “gem” hues.

What’s going on?

You and your child have recreated a natural process of crystallization.  When water evaporates from the brick surface, the molecules in the salt and the bluing mixture realign and “stick” to one another and the surface in crystalline form.  Pull out a magnifying glass for a closer look as the crystal forms—and enjoy!