Download CHAPTER 3: MINERALS

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WHAT IS A MINERAL
ALL MINERALS SHARE THE FOLLOWING 5 CHARACTERISTICS:
1. Naturally occurring: a mineral forms by natural geologic processes like
crystallization, evaporation or pressure and heat. Therefore cubic
zirconium is NOT a mineral but diamonds are.
2. Inorganic: made of non-living things. Halite (salt) is an example but sugar
is not because sugar comes from sugar cane a plant.
3. Solid: hard and breakable
4. Definite chemical composition: most minerals are chemical compounds
made of two or more elements like salt (NaCl). A few minerals, such as
gold and silver, consist of a single element (native form).
5. Definite crystalline structure: the atoms are arranged in orderly, repeating
patterns to form crystals
HOW DO MINERALS FORM?
1. Crystallization from magma: magma
is a molten rock. It forms deep within
the Earth. As magma cools,
elements combine to form minerals.
2. Precipitation: when water
evaporates out of lakes, rivers, ponds,
and oceans the dissolved substances
react to form minerals. Limestone
caves are formed this way also.
3. Pressure and temperature: existing
minerals are exposed to heat and
pressure and recrystallize into different minerals.
THE MOST COMMON ELEMENTS IN EARTH’S CURST
Over 4,000 minerals have been named and new ones are named each year. Only a
few dozen are known as common minerals. All minerals are classified into groups
based on their composition (the elements that make them up). Most minerals are
made up of two or more elements

92 elements are found in nature, but only 8 are in great abundance:
1. Oxygen (O)
_____
2. Silicon (Si)
_____
3. Aluminum (Al)
_____
4. Iron (Fe)
_____
5. Calcium (Ca)
_____
6. Sodium (Na)
_____
7. Potassium (K)
_____
8. Magnesium (Mg) _____
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MINERAL GROUPS
1. The Silicates…also called the “rock formers” because they make up most of the
rocks that we see
 All members of this family contain SILICON and OXYGEN (SiO)
 Quartz (SiO2) and Feldspar (KAlSi3O8) are the 2 most common minerals
in earth’s curst
 Mica (also a silicate) is another common mineral found in rocks
2. The Carbonates…contain the elements carbon, oxygen (CO3) and one or more
other metallic elements.
 Calcite (CaCO3) is the most common carbonate and dolomite
(CaMg(CO3)2) is another carbonate mineral that contains magnesium
and calcium.
 Carbonates fizz when HCL is dropped on it.
3. The Oxides…contain the element oxygen (O) and a metal.
 Hematite (Fe2O3) and Magnetite (Fe3O4) are examples of oxides
4. Other mineral groups include:
 Sulfides: minerals with sulfur (S) and one or more elements Ex: Pyrite
(FeS2)
 Sulfates: elements with the sulfate compound (SO2) Ex: Olivine
(Fe2SO4)
 Native elements: Smallest group, are made up of only 1 element,
Examples: Gold (Au), Silver (Ag), Copper (Cu)
AMAZING EARTH SCIENCE FACTS
 A ____________ is found in nature, inorganic, solid with a definite chemical
composition and structure
 Mineral properties such as hardness and cleavage depend on the
mineral’s _________________________________
 ___________ are minerals that are mined because they contain substances
that are useful and profitable…some ores are pyrite, galena, magnetite,
hematite, graphite and sulfur
 _____________________________---are the two most abundant elements in
Earth’s crust.