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Science Experiment: Charcoal Briquette Crystal Growing Project

Charcoal Briquette Crystal Growing Project

You will need: 1 charcoal briquette, 1 pie tin, Charcoal crystal solution (10ml Ammonia, 50 ml laundry bluing, 50ml salt, 100ml water)

  1. Mix a batch of crystal solution, stirring well. *For colorful crystals, add food coloring to the solution!
  2. Place a piece of charcoal into the pie tin. Pour crystal solution over the top of the charcoal.
  3. Over time, crystals will form on top of the charcoal. *Add more solution to the pie tin for continued crystal growth.


Charcoal is very porous and absorbs the solution. Water evaporates from the solution leaving salt crystals behind in this crystal growing project. Cave of the Mounds is a “living” solution cave. Water brings calcium carbonate into the cave. Crystals of calcite are deposited, creating cave formations called speleothems.

Photo of quartz crystals that can be purchased at this Must See Destination in Wisconsin