|MadSci Network: Chemistry|
I am a crayon and marker scientist for Crayola (Binney & Smith, Inc.) All crayons are made of wax. Since wax floats, all crayons should float. However, there is one more ingredient that goes into a crayon: PIGMENT (color)... Pigments come in all shapes and sizes. Some pigments are heavier (more dense) than water. If crayons have heavy pigments in them, then they will sink in water. Metallic crayons will sink, and some glitter crayons as well.
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