First Children's Encyclopedia by Dorling Kindersley - page 259

Creating concrete
Concrete is an important
building material. It is a
mixture of sand, gravel,
cement, and water. All
these ingredients are
found in the ground.
Getting gas
Gas is only found in certain
places. To get it to where it is
needed, it is fed through very
long pipes, or changed into
liquid and put in special ships.
Extracting metals
Most metals are found
underground as minerals
in rocks called ores. Giant
machines dig up the ore. The
metal is extracted, or taken
out, from the ore using heat.
Oil.
Gold
is rare and looks
attractive, so it is often
used to make jewellery.
Iron
is strong. It is used
to make steel for ships,
buildings, and pylons.
Copper
conducts
electricity and is used
to make electrical wires.
Aluminium
is a soft
metal used to make cans,
aircraft, and car bodies.
Metal variety
Different metal resources
have different uses.
257
Making glass
Glass is made by melting
together sand, soda ash, and
ground limestone. People blow
or machine press the red-hot
mineral mixture into different
shapes that set hard and
clear as the glass cools.
Glass bottles are shaped
from molten glass.
Resources in the ground
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