The document discusses minerals and their characteristics. It defines a mineral as a naturally occurring, inorganic solid with a definite chemical composition and crystalline structure. Minerals are the building blocks of rocks and are studied by mineralogists. The document outlines the key characteristics minerals must have and describes different types of minerals including silicate and non-silicate minerals. It also discusses how minerals form and can be identified based on their physical properties such as color, streak, luster, hardness, cleavage/fracture, and density.
3. CHARACTERISTICS OF A MINERAL
NATURALLY
OCCURRING
CRYSTALLINE
STRUCTURE
DEFINITE CHEMICAL
COMPOSITION
INORGANIC
HOMOGENOUS
SOLID
4. Coal is NOT a mineral because it comes from
plants
Amber is NOT a mineral because it comes from
tree sap
Pearls is NOT a mineral because it comes from
oysters
2. INORGANIC - NOT COMPOSED OF ORGANIC
MATTER; NOT FROM LIVING THINGS OR THE
REMAINS OF LIVING THINGS.
5. 3. Have a definite volume and a definite shape.
Stable and solid at room temperature
Mercury is not a mineral because
it is liquid at room temperature
HOMOGENOUS SOLIDS
6. Silicate Minerals
a) silicon and oxygen
groupings; SiO2
1) combined with one or
more metals
Talc- Mg3Si4O10(OH)2
2) Largest group of
minerals
1) 90% of the earth's crust
Non-silicate minerals
b) DO NOT contain SiO2
1) subdivided into several
other classes
2) Extremely rare
8% of the Earth's crust
3) Few are relatively
common
calcite
DEFINITE CHEMICAL
COMPOSITION
7. a) Native Elements –elements found in nature
in their mineral form.
gold (Au), sulfur (S), silver(Ag)
b) Sulfides – minerals that contain sulfur ions.
Galena (PbS), Pyrite (FeS2)
d) Sulfates - minerals which include the sulfate
ion (SO4
2-).
Gypsum (CaSO4·2H2O)
NON-SILICATE SUBDIVISIONS
8. d) Oxides - minerals that contain oxygen bonded
with one or more metals
Hematite (Fe2O3), Magnetite (Fe3O4)
minerals containing (OH) are typically
included in this class. (hydroxides)
Portlandite (Ca(OH)2)
e) Halides - minerals with that contain Fluorine,
Chlorine, Bromine and Iodine ions.
Halite (NaCl), Fluorite (CaF2)
NON-SILICATE SUBDIVISIONS
9. f) Carbonates – minerals that contain a
carbonate ion, CO2−
3.
Calcite (CaCO3), Dolomite (CaMg(CO3)2)
Many more subdivisions; each with chemical similarities
NON-SILICATE SUBDIVISIONS
10. 1. The internal structure or arrangement of
atoms within a mineral
Halite (NaCl)
2. Atoms/molecules are arranged in repeating
geometric patterns.
CRYSTALLINE STRUCTURE
11. a) Cubic - Galena, Halite, Pyrite
b) Tetragonal – Chalcopyrite
c) Hexagonal - Quartz, Calcite
d) Orthorhombic - Olivine, Topaz
3. SIX BASIC CRYSTAL SYSTEMS
12. e) Monoclinic – Mica, gypsum
f) Triclinic – Feldspar, Turquoise
SIX BASIC CRYSTAL SYSTEMS
13. 4. Minerals form
a) When lava or magma cools to solidification
b) When water evaporates and leaves minerals remain
c) When water is supersaturated with a mineral;
minerals will settle out of the water and deposit as a
precipitate.
MINERAL FORMATION
14. 1. Minerals can be identified by their physical and
chemical characteristics.
a) Physical Properties:
Color
Streak
Luster
Hardness
Cleavage or Fracture
Density
IDENTIFYING MINERALS
15. 2. Color: Not a reliable property; some minerals can
be many different colors.
a) Color may vary due to:
1) Natural coloring agents - impurities
2) Weathering; exposure to the environment
b) Malachite-green
c) Quartz-clear, purple, white, grey-brown…
d) Sulfur-yellow
e) Hematite-black, silver, reddish brown
PHYSICAL PROPERTIES
16. 3.Streak: The color of the mineral in
its powdered form.
a)Determined by using a streak plate
1) Quartz: White/colorless
2) Hematite: reddish brown
PHYSICAL PROPERTIES
17. 4. Luster: The way a mineral shines/reflects light
from its surface.
a) Metallic: reflects light like the surface of a
polished metal
1) Galena, Pyrite, Graphite, Magnetite…
b) Non Metallic: reflects light in more subtle ways
1) Pearly-Mica
2) Glassy-Quartz
3) Dull/Earthy-Bauxite
4) Waxy-Talc
5) Brilliant-Diamond
PHYSICAL PROPERTIES
18. c) When a mineral
scratches a substance;
it is harder than the
substance
PHYSICAL PROPERTIES
5. Hardness: A
measure of how
easily a mineral can
be scratched.
a) Determined by a
minerals internal
structure.
b) When a mineral is
scratched by a
substance; it is
softer than the
substance
19. TESTING HARDNESS
Hardness Name of Mineral
1 Talc
2 Gypsum
3 Calcite
4 Fluorite
5 Apatite
6 Feldspar
7 Quartz
8 Topaz
9 Corundum
10 Diamond
Common Objects
2.5 Fingernail
3.5 Copper
4.5 Iron Nail
5.5 Glass
6.5 Steel File
7 Streak Plate
Mohs Hardness Scale
20. 6. Cleavage: When a mineral splits/breaks
along smooth flat surfaces
a) Mica - One direction; sheet
b) Galena – Three; cubic shape
a) Determined by atomic structure
of mineral
1) Cleavage is the way a mineral
breaks
2) Crystal Shape is the way
crystal grows
PHYSICAL PROPERTIES
21. 7. Fracture: When a mineral breaks unevenly
into curved or irregular pieces with a rough
and jagged surfaces.
a) Sulfur, bauxite, hematite, quartz
PHYSICAL PROPERTIES
22. 8. Density or Heft: Minerals have different
densities, and vary in weight given the same
sample size.
How heavy the mineral feels in your hand
PHYSICAL PROPERTIES