Copyright 2006 Veta Sciences
Vaseline Glass
This type of glass is sometimes called "uranium glass" because it contains very small amounts of radioactive uranium dioxide.  And, because the radioactive element is part of the glass mix, the glass glows a vivid bright green color when exposed to short wave UV light.  This large gemstone was faceted by special request from a vaseline glass collector to be incorporated into his large collection.  The radiation level from this type of of glass is very low and safe for normal use.