Right you are - Prussian Blue is actually a pigment, supposedly derived from those used in old Prussian military uniforms but actually invented by an artist in Berlin in 1704. It is the "first modern, artificially manufactured color," which seems a bit ironic in view of the subject matter at hand.
I hope the kids learn better and they probably will. Racism is self-limiting and self-destructive no matter which way it's pointed.
