according to the what is known of the eye, light
travels through the cornea which is lying on the iris, and in the
middle of the iris, theres a small opening which is the pupil which
light will further down to the back of the eye.
with that knowledge, the iris is known to be the black part on
the eyeball. so you can try puttng glitters on the white part of
the eyeballs. the more glitters, the more it will sparkle.
