earth and life science grade 11 senior high school

2. Criteria for Judging
• Content 35
• Presentation 30
• Use of Language 20
• Clarity 10
• Time 5

3. Geosphere
Rocks Minerals
luster
streak
color
hardness
cleavage
specific
gravity
igneous
sedimentary
metamorphic
Is composed of…
Characterized by…
Classified into…

4. Mineral
•A naturally occurring, inorganic
solid with a definite chemical
composition and an ordered
internal structure

5. -Solid
-Inorganic
-Naturally-occuring
-Definite Chemical Composition
-Ordered Internal Structure
General Characteristics

6. Composition of Minerals
•1. Silicates
•2. Oxides
•3. Sulfides
•4. Sulfates
•5. Halides
•6. Carbonates
•7. Native Metals

7. Crystal Structure
•Dependent on the chemical
composition of the mineral.
Minerals that have similar
chemical composition often share
same crystal structure.

9. Physical Properties of Minerals
•There are around 4000 minerals
and each has a unique set of
physical properties.
•These properties are useful for
identifying minerals using a
systemic method.

10. Crystal Form and Habit
• Since minerals have a definite
chemical composition, it forms a
definite structure which crystallizes in
a specific crystal form.
• Habit is the outward appearance of
the mineral’s crystal form

11. Cleavage and Fracture
•The manner in which a mineral
breaks is dependent on its
molecular bonding and structure
•The tendency of a mineral to
break along planes of weakness is
known as cleavage.

13. Luster
• Describes the appearance of light
reflected from a mineral surface
• Metallic
• Non-metallic
Vitreous (glass-like) Greasy
Resinous (like resin) Silky
Pearlescent Earthy
dull

14. Color and Streak
•Streak is the color of a mineral
in its powdered form.

15. Hardness
•Measurement of the strength of
the chemical bonds in its
structure.
•Can be measured by scratching

16. Index Mineral Scale
Common
Objects
Index Mineral Scale
Common
Objects
diamond 10 apatite 5
corundum 9 fluorite 4
topaz 8 calcite 3
quartz 7 gypsum 2
orthoclase 6 talc 1
steel file(6.5)
glass (5.5)
wire nail (4.5)
copper coin (3.5)
fingernail (2.5)
MOHs SCALE OF HARDNESS

17. Density
• Specific gravity is a measure of the
density of a mineral
•It is the weight of a mineral relative
to the weight of an equal volume of
water

18. Other properties
•Magnetism - magnetite
•Taste - halite is salty
•Effervescence or reaction to acid –
calcite and other carbonates will
react with weak acid
•Feel - talc is greasy

19. Common Rock-forming Elements
•Oxygen 46.6 %
•Aluminum 8.1 %
•Calcium 3.6 %
•Sodium 2.8 %
■ Potassium 2.6 %
■ Magnesium 2.1 %
■ Iron 5.0 %
■ Silicon 27.7 %