
He was cooking
and selling CRYSTAL meth, Susan.
The Big Bang Theory Season 10, Episode 1

and I damn sure didn't say
anything about no CRYSTAL.
Breaking Bad Season 2, Episode 3

It's a silicon dioxide CRYSTAL,
otherwise known as quartz.
The Big Bang Theory Season 12, Episode 2

And this is a high-pulse laser
with a BBO CRYSTAL.
The Big Bang Theory Season 12, Episode 22

Crystal.
Breaking Bad Season 3, Episode 11