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today squeaks and i are looking at all
kinds of super strong rocks we can test
which rock is harder by scratching one
rock against another and seeing which
one doesn't leave pieces behind
oh
this rock isn't so strong because it
leaves some pieces behind when i scratch
it against the second rock and the
second rock is stronger because it
doesn't crumble one of the strongest
rocks of all though is one that you
might not expect it's a diamond
oh you're right squeaks diamonds aren't
exactly the same thing as rocks a
diamond is something called a crystal
that means it's solid and when you look
really close like with a special
microscope you can see that it's made up
of smaller pieces arranged in a special
repeating way rocks on the other hand
are made up of lots of different
crystals mixed together like the rocks
we have here if you mix together a
diamond and a bunch of other crystals
then it would be a rock but diamonds are
stronger than all the other rocks and
crystals in the world that's because of
the stuff diamonds are made out of and
how they form let's take a closer look
diamonds are made out of carbon a
special material that makes up all kinds
of things here on earth lots of rocks
contain carbon pencils and paper have
carbon in them and every single living
thing has carbon in it even you and me
but carbon looks different depending on
what other materials it's put together
with and how they're put together it's a
lot like how you can make lots of
different things with building blocks if
squeaks puts the same blocks together in
different ways they can be a tree or a
house or a mountain for carbon building
blocks to become a diamond they need to
be heated up really hot and smooshed
together super hard most diamonds formed
a really long time ago between one and
three billion years that's way before
there were dinosaurs on earth there
weren't even any plants yet most
diamonds also formed deep underground
about 150 kilometers down way farther
than the deepest hole anyone has ever
dug the earth is incredibly hot and made
of melted rock it's a bit like the
inside of a volcano some of the carbon
deep down there was heated up really
really hot and was squished together by
all the stuff on top of it we call that
squishing pressure with all of the heat
and pressure around it the tiniest bits
of carbon began to move around and stick
together holding each other in place
until there were bigger pieces of carbon
all stuck together can you guess what
those bigger pieces turned into squeaks
that's right it was the start of a
diamond because of the heat and the
pressure the carbon stuck together in a
very regular pattern that's a big part
of what makes diamonds so strong but
even after the carbon stuck together to
make the diamonds we know today they
were still really far underground then
something amazing happened some of the
molten hot insides of the earth erupted
towards the surface
it was just like a volcano squeaks only
these eruptions came from even deeper
underground than volcanoes today and it
happened much faster the eruptions
carried all kinds of materials from the
inside of the earth up to the earth's
crust the ground right near the surface
of the earth the diamonds were carried
up and when they reached close enough to
the surface of the earth the diamonds
and all of the other burning hot rocks
and other stuff around them cooled down
many of the diamonds stopped a little
bit below the surface and even after
they cooled down they stayed in their
special shapes billions of years passed
until people started to find diamonds in
the ground these days people dig up
diamonds to sell and use in things like
jewelry or special tools that need to be
made of one of the strongest materials
in the world that is one super crystal
thanks to one of our viewers rashab for
asking us about this what amazingly
strong rocks can you find where you live
are there any other tests you can think
of to see how strong rocks and crystals
like diamonds are we have a website
where you can send us your ideas just
ask a grown-up to help you go to
patreon.com scishow kids to check it out
and we'll see you next time here at the
fort
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you