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Individual work

Task 1. Read the text and translate it into Ukrainian (in written form).
Build up a list of key terms to the text.

Other Properties of Minerals
In addition to the properties discussed thus far, some minerals can be recognized
by other distinctive properties. For example, halite is ordinary salt, so it can be quickly
identified through taste. Talc and graphite both have distinctive feels; talc feels soapy,
and graphite feels greasy. Further, the streaks of many sulfur-bearing minerals emit
odors like rotten eggs. A few minerals, such as magnetite, have a high iron content and
can be picked up with a magnet, while some varieties (lodestone) are natural magnets
and will pick up small iron- based objects such as pins and paper clips. Moreover, some
minerals exhibit special optical properties. For example, when a transparent piece of
calcite is placed over printed text, the letters appear twice. This optical property is
known as double refraction. One very simple chemical test involves placing a drop of
dilute hydrochloric acid from a dropper bottle onto a freshly broken mineral surface.
Using this technique, certain minerals, called carbonates, will effervesce (fizz) as carbon
dioxide gas is released. This test is especially useful in identifying the common
carbonate mineral calcite.

Task 2. Answer the following questions:
1. What minerals can be identified through taste? Feel? Odor?
2. What minerals can be picked up with a magnet?
3. What is double refraction? What property does it represent?

Test yourself

Task: Tell whether the sentences are true or false. Correct the false ones.
1. How easily minerals break or deform under stress is determined by a high pressure
on them.
2. Minerals hat can be cut into thin shavings are described as brittle.
3. The tendency of a mineral to break along planes of weak bonding is called
cleavage.
4. Fracture is the tendency of a mineral to have chemical bonds that are equally, or
nearly equally, strong in all directions.
5. Density, an important property of matter, is defined as height per unit volume.
6. You can estimate the specific gravity of a mineral by hefting it in your hand.
7. Specific gravity is a number representing the ratio of a mineral’s weight to the
weight of an equal volume of mineral water.
8. Other distinctive properties of minerals are connected with taste, odor and feel.
9. All minerals exhibit special optical properties.
10. Some minerals have a high iron content.

UNIT 13
MINERAL GROUPS

Task 1. Read and memorize the following words:
manufacture - виробництво, extensively- широко
виготовлення; обробка; процес
виготовлення
exclusive - винятковий, особливий; in order of abundance – у порядку

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