Transcript Document

Minerals
A mineral is a naturally occurring, inorganic solid with distinct
physical and chemical properties.
Facts about minerals:
1. All minerals are composed of elements (substances made of
only one atom).
2. Minerals are homogeneous (they are the same throughout).
3. Most rocks have a number of minerals in common. In other
words, there are hundreds of minerals, but only 12 are
common and are found in different proportions in different
rocks.
Ms. Hartnett's Earth Science
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There are 7 properties that are used in identifying minerals:
1. Hardness – a minerals resistance to being scratched. This is
based on Moh’s Scale of Hardness which goes from to 1-10.
1 is the softest and 10 is the hardest. What mineral has a
hardness of 10?________________
2. Luster – the way a minerals surface reflects light. It is
either said to be metallic or non-metallic?
3. Streak – the color of the powdered form of a mineral. The
mineral is rubbed against a porcelain plate.
4. Cleavage – the tendency of a mineral to break along planes
of internal atomic weakness (how it looks when it breaks).
5. Specific Gravity – density of the mineral
6. Crystal Shape – the shape of a mineral, after it forms.
7. Color – this is the least useful and most unreliable of all of
the properties to use.
Ms. Hartnett's Earth Science
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Ms. Hartnett's Earth Science
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