It's a silicon dioxide crystal,
otherwise known as QUARTZ.
The Big Bang Theory Season 12, Episode 2
this tourmalinated QUARTZ
that we got in the lab.
The Big Bang Theory Season 7, Episode 13
Quartz, from the
German "quarz"
The Big Bang Theory Season 12, Episode 2
Oh, you forgot your QUARTZ.
The Big Bang Theory Season 7, Episode 13
And that stone in front--
I bet it's QUARTZ.
The Big Bang Theory Season 12, Episode 2