Page 216 - DK Children's Encyclopedia

Rocks and minerals SEE ALSO

▸ ▸ Earth’s surface
p.84

The Earth’s surface is made up of hard natural ▸ ▸ Elements p.90
objects called rocks. Rocks are made up of a mixture ▸ ▸ Gemstones
of substances called minerals. There are many p.118

different kinds of rocks and minerals. ▸ ▸ Metals p.162
▸ ▸ Rock cycle p.213

▸ ▸ Volcanoes p.268

Rocks Metamorphic rock
Types of rock have different Under great heat and pressure,
metamorphic rock is formed
names depending on how they deep inside the Earth.
were formed. The three types
are called sedimentary, igneous,
and metamorphic.

Sedimentary rock
When particles of minerals settle
and are squashed together, they
slowly become sedimentary rock.

Igneous rock
This type of rock is formed
when melted rock cools
down and becomes solid.

There are
Minerals nearly 4,000 Glowing rocks
A mineral is a naturally occurring solid. It is made different types Some rocks look plain in daylight, but
their minerals change color under
from chemical elements—simple substances of minerals special “ultraviolet” light. The glowing
that cannot be broken down further. Minerals on Earth. minerals in this rock are called calcite
grow together to form rocks. and willemite.

Serpentine Amethyst Garnet Opal
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