Answers to Go with Susan Smith

Q. I am a retired science teacher. I read your column on bluing. I have a suggestion for a follow-up article. Did you know that bluing can be used to make a ‘crystal garden’? I have directions for a crystal garden that works every time.

A. Librarians love retired teachers, they make great library volunteers!

This particular retired science teacher proved her worth by dropping by to pitch in and help at our huge eclipse-viewing party last summer.

Here are her directions for making a crystal garden with Mrs. Stewart’s Concentrated Liquid Bluing which can be ordered online if you have trouble finding it locally.

This project would be perfect for adults who would enjoy introducing a child to a classic science experiment.

Let’s begin with the science behind this activity. “Purpose: to observe the growth of fluffy crystals. Results: Fluffy crystals of different shapes will form on top of the charcoal. Some crystals will climb up the sides of the bowl.

“Explanation: There are different kinds of chemicals dissolved in the water. Also the mixture is ‘supersaturated.’ It holds more chemicals than can normally be dissolved in the water.

“As the water evaporates, a thin layer of crystals forms on the surface. These crystals are porous like a sponge and the liquid below moves into the openings.

“Water again evaporates at the surface leaving another layer of crystals. This continues, resulting in a buildup of fluffy crystals.”

Materials list:

  •  four or 5 charcoal briquettes that do not contain lighter fluid
  •  1 tablespoon plain (nonsudsy) household ammonia
  •  1 quarter cup distilled water
  •  1 quarter cup kosher salt or pickling salt (without iodine)
  •  1 quarter cup Mrs. Stewart’s Concentrated Liquid Bluing
  •  2 quart glass or plastic bowl (not metal)
  •  food coloring (optional)


  1.  Place the charcoal briquettes in the bottom of the bowl.
  2.  In a cup, mix the ammonia, water, salt and bluing. Stir the mixture well.
  3.  Pour the mixture over the charcoal briquettes. Add drops of food coloring, if you wish.
  4.  Allow the bowl to sit undisturbed for 72 hours. Place the bowl where it will not be moved because the crystals will fall off.

Note: this science teacher mentioned that not every set of crystal garden directions you might find elsewhere are as reliable as the instructions above.

San Marcos Daily Record

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P.O. Box 1109, San Marcos, TX 78666