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metallic resources. Halite is the mineral name for common table salt. Gypsum is the
mineral of which plaster and other similar building materials are composed.
Most nonsilicate mineral classes contain members that are prized for their
economic value. This includes the oxides, whose members hematite and magnetite are
important ores of iron. Also significant are the sulfides, which are basically compounds
of sulfur and one or more metals. Examples of important sulphide minerals include
galena (lead), sphalerite (zinc), and chalcopyrite (copper). In addition, native elements,
including gold, silver, and carbon (diamonds), plus a host of other nonsilicate
minerals—fluorite (flux in making steel), corundum (gemstone, abrasive), and uraninite
(a uranium source)—are important economically.

Task 2. Copy out all the names of the minerals, transcribe and translate
them.

Task 3. Answer the following questions:
1. Some of the most common nonsilicate minerals belong to one of three classes of
minerals. Will you name them?
2. When do we call the rock limestone?
3. When do we call the rock dolostone?
4. What is there in common between halite and gypsum?
5. What makes halite and gypsum different?
6. Try to prove that most nonsilicate mineral classes contain members that are prized
for their economic value. Provide the examples.

Task 4. Read the following text, translate it into Ukrainian. Answer the
question: what is the difference between mineral resources and just minerals?

Mineral resources
Resources include already identified deposits from which minerals can be
extracted profitably, called reserves, as well as known deposits that are not yet
economically or technologically recoverable. Deposits inferred to exist, but not yet
discovered, are also considered mineral resources.
The term ore is used to denote those useful metallic minerals that can be mined
at a profit. In common usage, the term ore is also applied to some non-metallic minerals
such as fluorite and sulfur. However, materials used for such purposes as building stone,
road aggregate, abrasives, ceramics, and fertilizers are not usually called ores; rather,
they are classified as industrial rocks and minerals.
Recall that more than 98 percent of Earth’s crust is composed of only eight
elements, and except for oxygen and silicon, all other elements make up a relatively
small fraction of common crustal rocks. Indeed, the natural concentrations of many
elements are exceedingly small. A deposit containing the average percentage of a
valuable element such as gold has no economic value, because the cost of extracting it
greatly exceeds the value of the gold that could be recovered.
To have economic value, an element must be concentrated above the level of its
average crustal abundance. For example, copper makes up about 0.0135 percent of the
crust. For a deposit to be considered as copper ore, it must contain a concentration that
is about 100 times this amount. Aluminum, on the other hand, represents 8.13 percent of
the crust and can be extracted profitably when it is found in concentrations only about
four times its average crustal percentage.
It is important to realize that a deposit may become profitable to extract or lose
its profitability because of economic changes. If demand for a metal increases and

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