Download 3-7-11 Aim: What is a Mineral?

Do Now:
Define Mineral.
HW: R&H pp. 218-222, A&E #1-15.
Study definition of mineral for quiz
tomorrow!
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Naturally occurring- happens on its own in
nature without human assistance.
Inorganic- not living and is not made of living
things.
Solid- definite shape and definite volume
Definite chemical composition- the same mix
of elements all the time.
Definite crystal structure- atoms arranged in
a repeating pattern that forms a crystal
shape.
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Color- what color the mineral appears- not the
best test because many minerals have the same
color and impurities may affect the color.
Streak- shows the mineral in its powdered form
against a white tile. A better sense of the
minerals color.
Luster- the way a mineral reflects light. There
are many lusters but we will look it metallic
(looks and shines like metal) or nonmetallic (
does not).
Hardness- a minerals’ resistance to scratching.
Density- how compact the molecules are D= M/V.
Cleavage- the tendency of a mineral to break along
flat planes. A mineral can have 0,1,2,or 3 planes of
cleavage. A plane is a direction of break and if there
are 3 than the shape is cubic.
 Crystal Structure- the way the atoms are arranged
creates a definite repeating crystal shape.
 Special properties- some minerals have a distinct
smell, are magnetic, can glow in the dark or
something else unique to the mineral that helps to
identify it. Also some minerals will react with certain
chemicals i.e. hydrochloric acid will fizz in the
presence of calcite.
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Do Now: Read p.219 “Mineral Crystal
Structure” and diagram on p.220.
1. What is a tetrahedron?
2. What is a tetrahedron made up of?
3. What is the tetrahedron responsible for?
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HW- R&H pp. 223-226, Finish lab.
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Do NowR&H pp.223-226.
1. How do sedimentary rocks form?
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HW- Finish Mineral ID lab.
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Monominerallic- rocks containing one
mineral type only (can be both a mineral and
a rock.
Polyminerallic- most rocks contain a mixture
of minerals, not in definite amounts.
Rock Types- there are three types of rocks
that differ in their environment of formation
(R.T. p.6). Sedimentary, Igneous,
Metamorphic.
Sedimentary rocks are formed at or near the
earth’s surface, usually under large bodies of
water.
 Sediments are deposited, buried by other
sediments forcing them to compact. Then
minerals dissolved in the water work as a glue to
cement the sediments together creating a
sedimentary rock. See R.T. p.7 for these rocks.
 The sediments can be broken pieces of other
rocks, shells, plant and animal remains, or
chemical precipitates or evaporites ( the solid
left after water evaporates).
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Texture – grain size- measure the size of the
grains in the rock (clay, silt, sand, pebbles,
etc.)
Layers of sediment.
Cemented together……….. Could be
sediments, shells, fossils or crystals from
chemical precipitates or evaporites
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Do Now:
1. What is an evaporite and give an example of a
rock that results?
2. What is a precipitate and give an example of a
rock that results?
3. What are the two organic sedimentary rocks
on the R.T.?
4. How does an igneous rock form (use
ref.table)?
HW- Finish Igneous Rock Lab
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What determines the size of the crystals in an
igneous rock is how fast the magma cools.
The longer it takes to cool the bigger the crystals
have an opportunity to grow.
Rock cools slowly deep below the surface
creating large intergrown crystals.
Rock cools quickly at the surface forming small
to no crystals.
Quiet lava flows produce glassy igneous rock
(non-crystalline), while explosive eruptions
produce vesicular rock (containing gas pockets)
If the cooling rate of magma gets interrupted by
another lava flow you can get a rock that has
fine crystals with larger ones mixed in
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1.
2.
3.
Do Now:
Where and how does a rock with large
intergrown crystals form?
As cooling time increases crystal
size_______.
How does a metamorphic rock form?
HW: R&H pp.226-232, A&E # 16-37.
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Can form deep underground where the heat and
pressure is great causing recrystallization
without true melting.
Rocks are distorted in structure- could be crystal
distortion, fossil distortion, layer distortion
Rocks are baked under the heat and pressure
and become foliated (the appearance of
peelable layers), could be fine, medium or
course foliation.
1.
2.
Regional Metamorphism- when a large area is pushed
further down in the crust resulting in tremendous
heat and pressure.
Contact Metamorphism- when rock comes in contact
with an igneous intrusion the rock touching the
intrusion gets heated and pressurized creating zones
of metamorphic rock.
Do Now: R&H pp.234-237
1. Answer aim question.
2. What is a renewable vs. a nonrenewable
resource?
 3. What is a fossil fuel and are they renewable or
nonrenewable?
 4. Why does metamorphic rock tend to be more
dense than the other types of rock?
 5. What is foliation?
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HW: A&E p.237 #38-47, study T.11 for exam
Monday.