Experiment #21 was an older formula consisting of NS-137 Ill-umanati and a translucent white base. We have brought this experiment back for further testing with-in the formula. Northstar produced some hand pulled tubing as well as Experimental #21 Opaque rods. These tubes are raw color that vary slightly with translucency. This glass is a translucent lime color with a bright green UV reactivity and luminesces best with a 365nm-395nm LED flashlight. This glass does contain uranium.