Earth Science
Minerals
Merrill Chapter 3 Notes
3-1 What is a mineral?

Mineral- a naturally occurring, inorganic solid, with a definite structure and composition.
90 naturally occurring minerals

Mineral Characteristics:
1. Formed by natural processes
2. Inorganic
3. Solids
4. All minerals are either an element or a compound with a unique chemical composition.
5. Atoms in the minerals are arranged in patterns that are repeated over and over again.

Structure:
Crystal- is a solid in which the atoms are arranged in repeating patterns. (page 63)
Six major crystal shapes (page 63)

Formation: Several ways that minerals can form.
1. Formed directly from cooling magma.
2. Can be formed when the water the minerals are dissolved in evaporates. (salt water)

Minerals are the building blocks of rocks.
98% of the Earth's crust is made up of only 8 elements (in the form of compounds called minerals)
The most common rock building minerals are feldspar and quartz (both silicates) and calcite, a carbonater.

Silicates-are minerals that contain silicon and oxygen and usually one on more other elements. Silicon and oxygen are the two most abundant elements in the earth's crust.

Merrill Chapter 3 Notes
3-2 Mineral Identification

Physical properties: these properties are used to identify individual minerals.

1. Hardness- the measure of how easily a mineral can be scratched. See Table 3-3.
2. Luster- describes how light is reflected from a mineral's surface.
3. Color-
4. Streak- is the color of the mineral when it is broken up and powdered.
5. Cleavage- breaking along smooth, flat surfaces.
6. Fracture- breaking with rough or jagged edges.

Other properties include magnetism and how it reacts to acids.

Merrill Chapter 3 Notes
3-3 Uses of minerals

Gems or gemstones- are highly prized minerals because of they are rare and beautiful.

Ores- a mineral is an ore if it contains a useful substance that can be mined at a profit.
-If cost of waste rock becomes too great then the value of the desired mineral, then is no longer classified as an ore.

-Value of an ore changes with its supply or demand.

Merrill Chapter 3 Notes
3-4 Asbestos Removal

Asbestos-a mineral with threadlike, flexible fibers.
1. Doesn't burn well
2. Doesn't conduct heat or electricity very well.

If the threads break lose they can float in the air and may be inhaled!
Inhalation of asbestos can cause serious diseases including cancer.

The type of asbestos are used in buildings has curly fibers that don't allow it to get in to our lungs.