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Macaroni Made (AND Science!): Borax Crystals

This activity is an oldie but goodie-perfect for Valentine's Day and the Gem Show!

By Kindle Rising, Publisher, Macaroni Kid East Tucson February 7, 2013

This crystal craft/science experiment also seemed perfect for Gem Show week.  I've seen it done with snowflakes, but in honor of Valentine's Day, I decided to try a crystal heart and my daughters' initials as well!  

Materials-

  • White pipe cleaners
  • Wide-mouth glass jars
  • Borax (found in the laundry aisle)
  • String
  • Pencil
  • Boiling water
  • Food coloring (optional)

How to:

  1. Twist your pipe cleaner into a heart shape (or whatever shape you like).  Make sure the shape will fit into your jar without touching the bottom or sides.
  2. Tie a string around part of your shape and then tie the string to a pencil.
  3. Use the pencil to suspend the shape into your jar. Try it out while the jar is still empty to make sure it hangs correctly.
  4. Remove your pipe cleaner shape, and add boiling water to the jar.
  5. Spoon in Borax, 1 TBs at a time, stirring to dissolve.  (Use about 3 Tbs per cup of water).
  6. Add food coloring if you like.
  7. Suspend your shape into the Borax solution.

  • Allow to cool overnight.
  • Remove and enjoy your sparkly crystals!

How does this work?

Here's a brief summary of the science behind this little project (because you KNOW your children will ask)!

Borax is a crystal (as are sugar and salt) that dissolves in water.  Hot water can dissolve more of these crystal solids than cold water, because heated water molecules move farther apart, making more room for the dissolving substance.  As the water cools, the the molecules become closer again, and there is less room for the dissolved substance.  So, the water begins to "let go"of the extra substance and crystals begin to form.  Different types of crystals dissolve and re-crystalize at different rates and in different ways. Borax re-crystalizes faster than sugar or salt, for example, and does so by forming many crystals on top of one another, which when the light refracts on them, makes the pipe cleaners look sparkly!