Polymer clay Sculptor Dinko Tilov uses glow-in-the-dark clay for skeletons because of its bone color. You can also use GITD clay instead of white for eyes or teeth in sculptures.
Several brands carry glow-in-the-dark clay. Some feel that Fimo's is the brightest. Sculpley III offers four colors of GITD clay-green, orange, blue and yellow. Liquid Poly Glo is a glow-in-the-dark liquid clay available in six colors.
It is possible to mix your own color of GITD clay-just add a tiny pinch to any standard glow clay. Be aware, though, that if you add too much color, you'll greatly diminish the glow.