(MUSIC)
JOAN CARTAN-HANSEN, HOST: A
ROCK IS A MATERIAL MADE UP OF
ONE OR MORE MINERALS.
AND MINERALS ARE MADE UP OF
COMBINATIONS OF 92 ELEMENTS,
SOME ARE MADE OF JUST ONE
ELEMENT, LIKE GOLD
OR DIAMONDS.
THESE MINERALS ARE RARE, SO
THEY ARE MORE VALUABLE.
OTHER MINERALS ARE FOUND IN
COMBINATIONS OF ELEMENTS.
THE FELDSPAR GROUP ARE THE
MOST COMMON MINERALS ON THE
SURFACE OF THE EARTH.
BUT IF YOU LOOK AT THE ENTIRE
PLANET, THE MOST COMMON
MINERAL ON EARTH IS
BRIDGMANITE.
IT MAKES UP ABOUT 38 PERCENT
OF THE EARTH'S VOLUME.
IT'S MADE OF MAGNESIUM, IRON,
CALCIUM AND SILICA AND IS
FOUND ONLY IN THE MANTLE, NOT
ON THE EARTH'S SURFACE.
SO FAR, SCIENTISTS HAVE
IDENTIFIED OVER FIVE THOUSAND
DIFFERENT MINERALS.
AND MINERALS AREN'T JUST FOUND
IN ROCKS.
YOU NEED MINERALS IN YOUR BODY
TO STAY HEALTHY.
YOUR BLOOD IS RED BECAUSE OF
THE IRON OXIDE IT USES TO
CARRY OXYGEN
AND YOUR BONES CONTAIN THE
MINERAL CALCITE.
FOR MORE INFORMATION ABOUT
GEOLOGY CHECK OUT THE SCIENCE
TREK WEBSITE.
YOU'LL FIND IT AT SCIENCE TREK
DOT ORG