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Minerals
Matter
Matter
is anything that has
volume and mass
 Solid-
definite shape and
volume
 Liquid- only definite volume
 Gas- neither definite shape or
volume
Matter is made of…
Element-
cannot be broken
down into simpler substance
by chemical or physical
means
Periodic Table
 Elements
are visually
represented on the Periodic Table
 Symbol- letter(s) representing
name of element
 Atomic number- above symbol
(# of protons)
Elements are made of…
 Atom-
the smallest particle of
matter that contains the
characteristics of an element
 Atomic
mass- protons AND
neutrons
 Atomic #- number of protons
#
of protons = # of electrons (but
ONLY protons are in nucleus,
electrons orbit around the nucleus)
 Atoms of the same element
ALWAYS have the same # of
protons
Atom model
Isotope
 Atoms
that have the same # of
protons, but different numbers of
neutrons
 Therefore, the mass number is
different

FYI- all atoms have the same atomic #
BUT may have multiple isotopes (each
with different mass #s)
Isotopes…which element?

http://images.encarta.msn.com/xrefmedia/aencmed/targets/illus/ilt/T046738A.gif
Bonding of Atoms
 Bonding-
atoms combine to form
compounds- they either gain,
lose or share electrons
 Compound- substance that
consists of two or more elements
that are chemically combined in
specific proportions
Minerals

All minerals must meet these 5
criteria:
1.
2.
3.
Naturally occurring- formed by
natural geologic processes
Solid- definite volume and shape
Orderly crystalline structureatoms or ions are arranged in an
orderly & repetitive manner
Definite chemical compositionchemical compound made of 2
or more elements
5. Inorganic- not made of living
or previously living
compounds
4.
How Minerals Form
 Crystallize
from magma- as
magma cools, elements combine
 Precipitation- water evaporates,
or changes temperature,
minerals are left behind
 Recrystallization-
Changes in
pressure & temperature, or
atoms are rearranged creating
new minerals
 Hydrothermal solutions- hot
solutions chemically change
minerals into new minerals
Mineral Groups
 Common
minerals are grouped based
on composition
 Silicates-
(most common)
silicon (Si) & oxygen (O)
 Examples-
quartz, olivine, augite,
hornblende, mica, feldspars
 Carbonates-
(2nd most
common group) carbon (C), O
& one or more other elements
(usually a metal)
Examples-
calcite, dolomite
 Oxides-
O & 1 or more
elements (usually metals)
 Examples-
rutile (titanium oxide),
corundum (aluminum oxide),
hematite (iron oxide)
 Sulfates
sulfur (S)
& Sulfides- contain
Examples-
anhydrite, gypsum,
galena, sphalerite, pyrite
 Halides-
halogen ion (from
Group 7A on periodic table)
Examples-
(CaF2)
halite (NaCl), flourite
 Native
elements- exist in
relatively pure form
Examples:
 Gold (Au)
 Silver (Ag)
 Copper (Cu)
 Sulfur (S)
 Diamond and Graphite (C)
Properties for Identification
 Color-
not often reliable; small
amounts of different elements
give the same mineral different
colors

http://www.ayresdigitaldoodlings.com/images/WS%20Quartz%20Crystals.jpg
 Hardness-
measure of the
resistance of a mineral to being
scratched
 Can
be found by rubbing the
mineral against another mineral (or
object) of known hardness
 Mohs
Hardness Scale- minerals
are arranged on a scale from 10
(hardest) to 1 (softest)
 Streak-
color of mineral in its
powdered form
 Obtained
by rubbing mineral across
streak plate (unglazed porcelain
tile)
 Color of mineral may vary, but
streak does not
 Metallic minerals- dense, dark
streak
 Luster-
how light is reflected
from the surface of a mineral
 Metallic-
appearance of a metal
 Vitreous- glassy (like quartz)
 Submetallic- somewhat metallic
 Adamantine- diamond
 Pearly, silky, earthy
 Crystal
form- visible expression of
mineral’s internal arrangement of
atoms

http://www.thaigem.com/images/tg/images/buyer/mineral_crystal.jpg
 Cleavage-
tendency of a mineral
to cleave, or break, along flat,
even surfaces
 Fracture- minerals that do not
show cleavage when broken;
uneven breakage
 Density-
ratio of an object’s
mass to volume (a specific
mineral will always have the
same density)
 Distinctive
properties:
 Feel
 Smell
 Magnetic
 Transparent
 Chemically
reactive