Download Minerals

Minerals
Minerals
• Minerals are naturally
occurring, solid,
crystalline, inorganic
substances with a
definite chemical
composition.
Minerals
• Minerals might be
made of one element,
such as:
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Gold
Silver
Copper
Diamond
Minerals
• …but most minerals are
made of more than one
element combined
together:
– Ruby = Al2O3 + Cr
– Emerald = Be3Al2(SiO3)6
– Feldspar = KAlSi3O8 –
NaAlSi3O8 – CaAl2Si2O8
– Sapphire = Al2O3 + V, Ti,
or Fe (for purple, white,
or yellow/green)
– Halite = NaCl
Minerals
• Most minerals end in
the word “ite” to
identify it as a mineral.
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Malechite
Hematite
Magnetite
Pyrite
Halite
Graphite
Wolframite
Minerals
• There are about 3700
different types of
minerals on the earth
that we know of, and
about 100 new minerals
are discovered each
year.
Minerals
• The most common
minerals on earth are:
– Quartz (most common
on Earth’s surface)
– Feldspar (most common,
in crust, but is a
combination of several
different types of
minerals.)
– Olivine (Most common
in the mantle)
Minerals
• The most rare minerals
in the Earth are:
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PAINITE (18 exist)
SERENDIBITE
POUDRETTEITE
GRANDIDIERITE
JEREMEJEVITE
RED BERYL
TAAFFEITE
BENITOITE
Birthstones
• Most birth
“stones” are
actually
minerals.
• Some months
have a birthstone
and a birth
gemstone
because not all
minerals work
well for jewelry
Mineral properties
• Minerals are identified
by the properties that
they have.
• Just like each element
has it’s own set of
properties that help
identify it, each mineral
has it’s own properties.
Minerals - properties
• Luster tells how well a
mineral reflects light.
• A minerals luster might
be:
– Metallic (shiny like a metal)
– Nonmetallic (not very
shiny)
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Waxy
Vitreous (glassy)
Pearly
Oily
Adamantine (brilliant like
diamond)
Minerals - properties
• Hardness
describes how
hard it is to
scratch the
mineral.
• The Moh’s
hardness scale is
used to find the
hardness of a
mineral.
Minerals - properties
• Cleavage describes how
the mineral breaks.
(Does it break along
certain planes?)
Minerals - properties
• Color is important in
identifying most
minerals.
Ruby
Sapphire
Minerals - properties
• But color can be
deceptive
Minerals - properties
• Streak is the color that
the mineral is when it is
a powder.
• A streak plate is used to
find a minerals streak
color.
Minerals - properties
• Other properties that
might be used to
identify minerals
include:
– Magnetism (tiny bits
of magnetite in
migrating birds)
– Reaction with certain
chemicals
– Smell
– Taste
– Flourescence
– Crystal structure
Minerals  Rocks
• Minerals combine to
form rocks
• Mineral + mineral = rock
Rocks
• Rocks don’t have a
definite chemical
composition like
minerals do because
they’re made of lots of
“pieces” of different
minerals all hooked
together.
Rocks
• There are 3 main types
of rocks:
– Sedimentary
– Igneous
– Metamorphic