Here are the possible solutions for gem that can diffract light clue
Answer
Clue
Relevancy
opal
Clue
Gem that can diffract light
Gem that can absorb water
Definition
an amorphous variety of silica
catseye
Clue
Light-reflecting gem
pearl
Clue
Gem whose authenticity can be checked by rubbing it against the teeth
Definition
to adorn with a milky-white concretion of nacre
icome
Clue
"Can ___? Can I? Can I?"
plea
Clue
"Can I? Can I? Can I?" e.g.
Definition
to dispute in a court
glorybeam
Clue
"The light" of "I saw the light!"?
laser
Clue
Light in a light show
Definition
a source of high-intensity optical, infrared, or ultraviolet radiation produced as a result of stimulated emission maintained within a solid, liquid, or gaseous medium
