Crayons under a spectrophotometer

Photographer Mark Meyer did a partial analysis of his crayons:

Starting with a fresh box of twenty-four Crayola crayons I measured each with an i1 pro spectrophotometer to create a set of spectral power distributions (SPD) of the reflected light….

This is what a box of crayons looks like broken into it’s spectral components.

(HT Bob O’Hara)