Ch.3 Minerals Study Guide
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Friedrich Mohs invented a system to describe and compare hardness of minerals
A vein is a narrow channel or slab of a mineral that is sharply different from the surrounding
rock
The purpose of heating iron ore to a very high temperature in a blast furnace is to heat the iron
so that it separates from other elements in the ore
Hard, colorful minerals that have a brilliant or glassy luster are gemstones
Steel is an example of a useful alloy
A mineral that splits apart easily along flat surfaces has the property called cleavage
Color alone cannot be used to identify a mineral because only a few minerals always have their
own characteristic color
Earthy, shiny, waxy, metallic, and pearly are terms used to describe a minerals’ luster
The size of a mineral’s crystals depends on the rate of cooling of the magma or solution from
which the mineral formed
Metallic is NOT one of the six types of crystal shapes
In the process called smelting, an ore is melted to separate the useful metal from other
elements in the ore
The property of density is the mass of the mineral sample per unit volume
A(n) shaft mine is used when ore deposits occur in veins
Table salt is made from deposits of the mineral halite
A rock that contains a metal or economically useful mineral is called a(n) ore
A miner is anyone who searches for an ore deposit; F = prospector
Minerals form when a hot water solution cools and the minerals crystallize; T
The mineral silver is used in the making of glass; F = quartz
A substance is organic if it did not arise from materials that were once part of a living thing; F =
inorganic
The vast majority of minerals are compounds; T
What characteristics does a piece of quartz have that can be used to classify it as a mineral
o Quartz occurs naturally, is inorganic, is a solid, has a crystal structure, and has a definite
chemical composition
In what two general ways do minerals form? Give an example of a mineral that forms in each
way
o In general, minerals form through crystallization of melted materials and through
crystallization of materials dissolved in water. An example of the former is silver; an
example of the latter is halite, gypsum, or calcite
Prospectors have discovered a halite deposit near the Great Salt Lake in Utah. Describe how
that deposit might have formed
o The halite deposit might have formed through the evaporation of salt water from the
Great Salt Lake
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Explain what slag is and how it forms
o Slag is a combination of impurities in iron ore and limestone. It forms in a blast furnace
once the iron in iron ore has melted and sunk to the bottom of the furnace
When feldspar breaks apart, it splits easily at right angles. When quartz breaks apart, it
produces curved, shell-like surfaces. What properties are being tested here? Is the way a
mineral splits or breaks apart enough to enable you to identify it? Why or why not?
o The splitting of feldspar at right angles is evidence of the property of cleavage, which
only some minerals have. The breaking of quartz into shell-like surface is evidence of
fracture, a property of most minerals. Neither property alone is enough to enable you to
identify a mineral, because other minerals also have these properties, though fewer
have the property of cleavage