Unit 4
Chapter 2
Minerals
Mr. Cesaire
Martin Van Buren High School
• Aim: What is a mineral?
• Do Now: Open to page 96 of the Earth Science
TEXT book and define mineral and write down
the characteristics of a mineral in your notes:
• HW: Read pages 47 to 51. Answer questions 1-8
on page 52. WRITE OUT ALL QUESTIONS!
• We will have a weekly quiz based on reading
assignments in UPCO. Quiz will be based on
pages 47 to 51.
Minerals
• What is a mineral?
• Defined as a naturally occurring inorganic
solid substance.
• Where do we find minerals in our
environment?
• Minerals are commonly found in rocks,
soils, and sand.
Minerals
• Where else in our homes do we find
minerals?
• Watches
• Clocks
• Pencils
• Glassware
• Read page 97 of your text and write down
the ways minerals are formed in your
notes.
Mineral Formation
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How do minerals form?
Minerals are formed by crystallization:
1. Cooling and solidification of magma.
2. From water- evaporation, chemical
reactions and temperature changes
3. Minerals subject to change due to heat
and pressure.
Common Minerals
• The back of our reference tables contains
information for common rock forming
minerals.
• What are some information do the
reference tables tell us about minerals?
• Describe
the
physical
and visual
properties
of Biotite.
Potassium Feldspar
• Describe the
properties of
Potassium
Feldspar.
Halite
Describe
the
properties
of halite.
• Aim: How are minerals identified?
• Do now: Use the reference tables and
answer the following set of questions.
• HW: .
• Quiz on Wednesday. The characteristics of
a mineral and the ways to identify them
Mineral Identification
• How do we identify minerals?
• Minerals are identified by their physical
and chemical properties.
• Experienced geologists can easily identify
and classify minerals out in the field. They
have achieved this ability through careful
observations of the minerals physical
properties.
• Open up to page 104 of your text book
and glance through pages 104 to 107 and
list and write a short sentence on the ways
minerals are identified in your notes.
Mineral Identification
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Geologists use the following to help identify
minerals:
1. Color- the apparent color of the mineral
2. Luster- Luster refers to how light reflects off
the surface of a mineral
3. Streak- The streak refers to the powder left
by the mineral when applied to a hard surface.
4. Hardness- The hardness of a mineral is
referred as the resistance to being scratched.
5. Cleavage- Cleavage refers to how minerals
break along parallel planes.
6. Specific gravity
7. Chemical Tests
Color
• Color: When observing a mineral, the first
thing that we notice is its color. The color
may give us clues to what type of mineral
we are looking at.
• However you can not go on color alone
• Let’s look at two examples: Quartz and
Calcite
Color
• Notice how quartz is similar in color.
• Some minerals may have the same color,
so we use other characteristics.
http://www.sci.ccny.cuny.edu/~kblock/minerals/quartz.jpg
http://www.sci.ccny.cuny.edu/~kblock/minerals/calcite.jpg
Color
• Quartz can appear in three colors:
• Rose, Clear, Smokey
•
http://www.pitt.edu/~cejones/GeoImages/1Minerals/1IgneousMineralz/Quartz/Quartz_3Types.jpg
Luster
Sulfur- Nonmetallic
http://resourcescommittee.house.gov/subcommi
ttees/emr/usgsweb/photogallery/thumbnails/Sulf
ur_jpg.jpg
Galena-Metallic
http://resourcescommittee.house.gov/subcommittees/emr/usg
sweb/photogallery/images/Galena%202_jpg.jpg
Streak
• Notice the
streak or
powder left
by galena
• Each
mineral has
a distinctive
streak.
http://www.visualsunlimited.com/images/watermarked/31
1/311404.jpg
Cleavage
http://www.sci.ccny.cuny.edu/~kblock/minerals/calcite.jpg
http://www.geology.sfasu.edu/minerals/galena01.jpg
Cleavage
Potassium
Feldspar