The world around us
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Minerals exist in the Earth’s crust. They can exist on their own and they can combine with other minerals to
make rocks. For example, granite is a rock which is made of the minerals feldspar, quartz and mica.
Minerals have different
properties
.
Minerals can exist in
crystal
form. The crystals are different shapes. Sometimes we can see the crystals.
But sometimes we can’t. We can see the crystals in quartz but not in malachite.
Lustre
Some rocks and minerals are shiny and some are dull. This is their lustre.
Gemstones
and metals, such as
gold and copper, are usually shiny. Graphite, which we use for making the lead in pencils, is dull.
Minerals are different colours. Sulphur is
yellow, copper, in mineral form, is green, and
cobalt is blue.
Colour
Hardness
Which mineral
can cut glass?
1
What minerals can you name?
R E A D & T H I N K
Some minerals are hard and others are soft.
Talc and mica are soft but diamonds are very
hard. We use diamonds to cut things. Diamond
is the hardest substance on Earth.
Other soft rocks and minerals include chalk,
silver, talc and mica. Hard ones include
slate
,
quartz
and
malachite
malachite
quartz
Minerals
