Sprout: The crystals didn't like this metallic pipe cleaner.
Me: Yeah, they seem to prefer natural materials over synthetic ones, man-made things.
Sprout: Human-made, Mom. You don't know if a man or a woman made them.
Right you are, Sprout. :P
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We set up three different solutions: 1) Borax 2) Epsom salts, and 3) Borax and Epsom salts. Both 1 and 2 grew crystals, but the mix of Borax and Epsom salt, tested both hot and cold, didn't "grow" anything and nothing has formed upon evaporation.