this tourmalinated QUARTZ
that we got in the lab.
The Big Bang Theory Season 7, Episode 13
Oh, you forgot your QUARTZ.
The Big Bang Theory Season 7, Episode 13
Okay, so it's QUARTZ.
The Big Bang Theory Season 12, Episode 2
It's a silicon dioxide crystal,
otherwise known as QUARTZ.
The Big Bang Theory Season 12, Episode 2
What do we know
about QUARTZ?
The Big Bang Theory Season 12, Episode 2