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Chapter 3: Minerals of the Earth’s Crust
Section 1: What is a Mineral?
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Section 1 What Is a Mineral? Chapter 3
Mineral Structure
• A Mineral is a
• 1. naturally formed, (found in nature)
• 2. inorganic (Not made of once living things)
• 3. solid that has a . . .
• 4. definite crystalline structure.
• You can tell whether an object is a mineral by
asking the following four questions…
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Section 1 What Is a Mineral? Chapter 3
Mineral Structure, continued
• Is it a nonliving material?
• Is it a solid?
• Does it have a crystalline structure?
• Is it formed in nature?
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Section 1 What Is a Mineral? Chapter 3
Mineral Structure, continued
• To understand what a crystalline structure is, you
need to know a little about the elements that make
up a mineral.
• Elements are pure substances that cannot be
separated or broken down into simpler substances
by chemical means. The elements are found on
the Periodic Table of Elements found on the back
wall and p. 794-795 in textbook.
•Solids: Black type; Liquids: Blue type; Gases: Red
(grouped by states of matter found at room temp.)
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Section 1 What Is a Mineral? Chapter 3
Elements
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Section 1 What Is a Mineral? Chapter 3
Mineral Structure, continued
• Atoms and Compounds Minerals may be either
elements or compounds.
• A compound is a substance made of atoms of
two or more different elements joined by chemical
bonds.
Example:
Element: Na & Cl (two elements)
Compound: NaCl (one compound)
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Section 1 What Is a Mineral? Chapter 3
Mineral Structure, continued
• A mineral that is composed of only one element is
called a native element.
• Gold and silver are examples of native elements.
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Section 1 What Is a Mineral? Chapter 3
Mineral Structure, continued
• Solid, geometric forms of minerals produced by a
repeating pattern of atoms that is present through-
out the mineral are called crystals.
• A crystal’s shape is determined by the arrangement
of the atoms within the crystal.
• The arrangement of atoms in turn is determined by
the kinds of atoms that make up the mineral.
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Crystals are orderly stacks of atoms. Here we see sodium atoms
(blue) and chlorine atoms (green) stacked in a way that makes
a microscopic cube. This cubic structure continues to grow
until your eyes can actually see a cubic crystal of salt. You
can't shape this crystal because when struck, the cube just
breaks into smaller cubes. Breakage is easier along the crystal
planes, which run same direction as the surface of the crystal.
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**Watch Brain Pop Video:
CRYSTALS**
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Section 1 What Is a Mineral? Chapter 3
Two Groups of Minerals
• Minerals are divided into two groups based on their
chemical composition.
• Silicate minerals are minerals that contain a
combination of silicon (Si), oxygen(O), and one or
more metals.
• Examples of silicate minerals are quartz, feldspar,
and mica.
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Section 1 What Is a Mineral? Chapter 3
Two Groups of Minerals, continued
• Nonsilicate minerals are minerals that do not
contain compounds of silicon and oxygen. There
are six main classes of nonsilicate minerals.
• Native Elements
Gold & Silver
• Carbonates
Calcite
• Halides
Flourite
• Oxides
Corundum
• Sulfates
Gypsum
• Sulfides
Galena
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Page 69 of textbook: Classes of Nonsilicate
Minerals