An atom consists of a central positively charged nucleus surrounded by negatively charged electrons. The nucleus contains protons and neutrons. Atoms are the building blocks of elements, which make up minerals. Minerals have distinct physical properties like hardness, crystal structure, and color that allow them to be identified. The most common minerals that make up rocks include quartz, feldspars, micas, amphiboles, pyroxenes, olivine, calcite, and dolomite. Minerals are important as they contain elements necessary for life and make up economically valuable resources.

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Atoms
An atom is a particle of matter that
uniquely defines a chemical element.
An atom consists of a central nucleus that
is surrounded by one or more negatively
charged electrons. The nucleus is
positively charged and contains one or
more relatively heavy particles known as
protons and neutrons.

3. Atoms
Protons - positive charge +1 Neutrons - no charge
Have a mass of 1- unit Have a mass of 1- unit
Electrons- have negative charge (-1) & negligible mass

4. Atomic Mass & Number
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• Isotopes
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Atomic Number
The number of protons in an atom.
Atomic Mass
The number of protons + neutrons +electrons.
How isotopes of an element differ from one
another.
• Isotopes
> Atoms of the same element that have
different numbers of neutrons, yet still have
the usual number of protons for that particular
element.

5. Isotopes
Isotopes

6. • Discuss elements in the periodic table
which constitutes the formation of
minerals
• Identify minerals using their physical and
chemical properties
(S11ES-Ib-1-3)
Objectives

7. •
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Elements
A substance that cannot be
broken down into simpler
substances by chemical means.
An element is composed of atoms
that have the same atomic number,
that is, each atom has the same
number of protons in its nucleus as
all other atoms of that element.

8. Periodic Table of Elements
Periodic Table of Elements
• table 2-2, p. 23

12. Ions
Ions
• atoms or groups of atoms that have an electrical
charge
- results from gaining or losing electrons
• Anion
- negatively charged atom
- e.g. Cl, O2,
• Cation
- positively charged
- e.g. Na, K, Fe2
• Complex
- a group of atoms with a charge
- e.g. SO4, CO3
• atoms or groups of atoms that have an electrical
charge
- results from gaining or losing electrons
• Anion*
- negatively charged atom
- e.g. Cl, O2,
• Cation*
- positively charged
- e.g. Na, K, Fe2
• Complex
- a group of atoms with a charge
- e.g. SO4, CO3

13. Chemical Bonds- control many physical properties
• Covalent
- Atoms share their outer-most electrons with another atom
- Very strong bond
• Covalent
- Atoms share their outer-most electrons with another atom
- Very strong bond
• Ionic
- Atoms get rid of electrons from their outer-most shell.
- results in a charged (+ or -) atom
- not as strong as above
• Ionic
- Atoms get rid of electrons from their outer-most shell.
- results in a charged (+ or -) atom
- not as strong as above
• Metallic
- A sea of electrons surrounding nuclei
- Electrons freely exchanged among atoms
- Metals make good conductors!
- can be strong
• Metallic
- A sea of electrons surrounding nuclei
- Electrons freely exchanged among atoms
- Metals make good conductors!
- can be strong
• Van der Waals
- electrostatic charge
- weak bond
• Van der Waals
- electrostatic charge
- weak bond

14. Carbon
Different chemical bond types result in different
minerals with different properties, despite being
composed of the same element

15. Characteristics of Minerals
Arrange the jumbled letters to find the appropriate criteria to determine whether a material is
classified as a mineral or not.
1. N L T L A U R Y N G O I R U C C
- It is a product of Earth’s natural processes.
2. C A I I R O G N
- It must be product of Earth’s physical
processes.
3. S O U E N E G O M O H D I L O S
- have definite shape and volume.
4.E N I L L A T S Y R C E S R T R U C U T
- atoms are arranged in order of increasing pattern.
5.L M C E H A I N O I T O C M O P S I
- represented by chemical formula

16. Minerals
Minerals
naturally occurring
excludes synthetic minerals
inorganic
non living processes form them
chemically specific
has a unique proportion of elements
crystalline solid
atoms are arranged in specific 3-D patterns
Definition:
Building blocks of rocks
Part of the Geosphere; found in Hydrosphere (hard
water); essential for Biosphere (life needs it!);
Atmosphere assists in alteration (weathering); Exosphere
provided raw materials (stars create elements).

17. What is a physical property?
Identify a physical property found in
minerals.

18. Physical Properties
Physical Properties of Minerals
• Color
• Luster
• Streak
• Hardness
- Moh's Relative Scale
• Crystal Habit
- The way it grows
• Cleavage or Fracture
- breaks into planes (flat surfaces)
• Density (Specific Gravity)
• Color
• Luster
• Streak
• Hardness
- Moh's Relative Scale
• Crystal Habit
- The way it grows
• Cleavage or Fracture
- breaks into planes (flat surfaces) or not
• Density (Specific Gravity)
• Related to the atomic
structure & type of
bonding

19. Color
Easiest to identify
Can be diagnostic (e.g., azurite = bright blue)
But commonly misleading due to extreme variability
impurities in between crystalline structure
impurities incorporated into the crystalline structure
Examples in Quartz
green blue yellow (citrine) pink (Rose)
purple
(Amethyst)
clear
(Rock
crystal)
brown
(Smoky)

20. Moh's Relative Hardness Scale
Moh's Relative Hardness Scale
Controls how resistant rocks are to erosion
1 Talc- (softest)
> Texas
2 Gypsum
> Girls (or Guys)
3 Calcite
> Can
4 Fluorite
> Flirt
5 Apatite
> And
1 Talc- (softest)
> Texas
2 Gypsum
> Girls (or Guys)
3 Calcite
> Can
4 Fluorite
> Flirt
5 Apatite
> And
6 Feldspar
> For
7 Quartz
> Quarters
8 Topaz
> They
9 Corundum
> Can
10 Diamond- (hardest)
> Dance
6 Feldspar
> For
7 Quartz
> Quarters
8 Topaz
> They
9 Corundum
> Can
10 Diamond- (hardest)
> Dance
3.5 copper penny
2.5 fingernail
5.0 streak plate*
5.5 plate glass*
6.5 steel file /nail*
* These items can be slightly harder or softer depepnding on how they were
made, and what is in them

21. Physical properties continued…
Cleavage vs Fracture vs Crystal shape
all related to chemical elements and types of bonds
Cleavage - the tendency to break along a plane
typically a zone of weak chemical bonds
Fracture - the tendency to break in non-planar surfaces
most notable is conchoidal fracture- curved conical
shapes common in quartz
Crystal habit- the 3 dimensional shape of minerals as
they grow- can be quite spectacular and diagnostic

23. Crystal examples
Peridot
Fluorite
Pyrite
Quartz

24. The mineral Quartz,
as well as some kinds
of rocks, exhibits this
unique kind of fracture

25. Other properties
Streak- the color of the powdered mineral against a
white background
Luster- the outer appearance- e.g. metallic,
and non-metallic such as: vitreous,, resinous, waxy,
greasy, pearly, silky, adamantine.
Special properties
taste, smell, reactivity to acids (HCl), magnetism,
pleochroism
Density- the weight per unit volume- a measure of how
closely packed the atoms are

26. Why are minerals physical properties
important?

27. Common elements in the crust
Silica (Si) - makes silicate minerals with oxygen
Oxygen (O) - makes silicate, oxide, carbonate, sulfate,
minerals when combined with other elements
Aluminum (AL) - a “garbage can” element- in many classes
Iron (Fe) - another “garbage can” element-in many classes
Magnesium (Mg) - another “garbage can” element-in many
classes
Calcium (Ca) - contributes to silicate species and
carbonates
Sodium (Na) - contributes to halide and silicates

28. Mineral Classes (1:2)
Mineral Classes
•
- Quartz, Feldspar, Biotite, Muscovite
•
- Hematite, Magnetite
•
•
• Silicates- Silicon-oxide Ion (Si O )
x
- Quartz (SiO2), Feldspar, Biotite, Muscovite
• Oxides- Oxygen (O )
x
- Hematite (Fe2O3), Magnetite (Fe2O4)
• Carbonates- Carbonate anion (CO )
3
2-
- Calcite (CaCO3), Dolomite, Malachite (Cu2(CO3)(OH)2)
• Sulfates- Sulfate anion (SO )
4
2-
- Gypsum (CaSO4) 2(H2O), Anhydrite, Barite
x - variable number of the element
x - variable number of the element
x
Native elements- Pure element
-
Gold, Silver, Copper, Sulfer
• Halides- F, Cl, Br, I
- Halite, Sylvite, Fluorite
Sulfides- Sulfur (S) anion
- Galena (PbS), Cuprite (CuS), Sphalerite ((Zn,Fe)S)
•
• Native elements- Pure element
- Gold (Au), Silver (Ag), Copper (Cu), Sulfur (S)
• Halides- contain F, Cl, Br, I anions
- Halite (NaCl), Sylvite (KCl), Fluorite (CaF2)
•
•
•

30. Importance as Rock Builders
Importance as Rock Builders
• All rocks are composed of Minerals.
• 12 or so are considered common.
> Olivine, Augite, Hornblende, Biotite
- darker colors- Green, Blue, Black, Brown
> Quartz,
>
> Muscovite, Calcite, Dolomite, Gypsum, Halite
- lighter colors- Pink, White, Yellow, Gray, Clear
• All rocks are composed of Minerals.
• 12 minerals are considered common.
> Olivine, Augite, Hornblende, Biotite
- darker colors- Green, Blue, Black, Brown
> Quartz,
> *Orthoclase, *Plagioclase (*feldspars),
> Muscovite, Calcite, Dolomite, Gypsum, Halite
- lighter colors- Pink, White, Yellow, Gray, Clear

31. Olivine
Augite
Hornblende
Biotite mica
Fe, Mg-rich Silicates

32. Quartz
Potassium
feldspar
(Orthoclase)
Plagioclase
feldspar
Muscovite
Quartz & Al-rich Silicates

33. Optical Calcite- CaCO3
shows double refraction.
Carbonates
Dolomite CaMg(CO3)2
rhombohedral crystal
White calcite CaCO3
note rhombohedral cleavage
in all three carbonate
samples shown

34. Halite—NaCl
Sulfides, Sulfates & Halides
Galena—PbS
forms of Gypsum-
CaSO4•2H2O
Selenite
Alabaster
Satin spar

35. Importance of Minerals
Importance of Minerals
•
> Na, Salt-NaCl > Cl, Salt-NaCl
> Fe, Hematite -Fe 2
O 3
> Mg, Dolomite-(Ca,Mg) 2CO3
> Ca, Calcite-CaCO 3
> K, Sylvite-KCl
•
> Au-Gold, Ag-Silver, Cu-Copper
> PbS-Galena (Lead)
> Fe2O3-Hematite (Iron)
> Al2O3-Corundum (Aluminum)
•
> Diamond- C, Aquamarine-Be3
Al2(Si6O18),
> Ruby, Sapphire-Al2
O3
• Contain elements essential for life.
> Na, Salt-NaCl > Cl, Salt-NaCl
> Fe, Hematite -Fe2
O3
> Mg, Dolomite-(Ca,Mg)2
CO3
> Ca, Calcite-CaCO 3
> K, Sylvite-KCl
• Economically significant
> Au-Gold, Ag-Silver, Cu-Copper
> PbS-Galena (Lead)
> Fe2O3-Hematite (Iron)
> Al2O3-Corundum (Aluminum)
• Aesthetically pleasing GEMSTONES!
> Diamond- C, Aquamarine-Be3
Al2(Si6O18),
> Ruby, Sapphire-Al2
O3

36. Where do rocks come from?
• Building blocks of all rocks are minerals
• Some minerals form as molten rock cools
• Some minerals form as chemical precipitates
• Some are produced by chemical reactions (weathering)
• Some are “manufactured” by living things
Biotite mineral grain
Biotite mineral grain
Feldspar
mineral
grain
Feldspar
mineral
grain
Quartz mineral
grain
Quartz mineral
grain