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Diamonds were formed by being 'squeezed together' and according to scientists, this happened
about a hundred million years ago. At that time there existed beneath the ground a mass of hot liquid
rock. The earth was in its early cooling stage, and in the process the mass of liquid rock was subjected to
extreme heat and pressure. One of the results was that certain chemical combinations were formed. And
one of these was highly crystallized carbon - what we call a 'diamond'.
Two of the most interesting things about diamonds are their hardness and their brilliance. A
diamond is actually about five times as hard as the next hardest substance on earth. Because a diamond
is so hard, getting it ready for use in jewelry is quite a complicated and skillful process.
First, a diamond is cleaved, or divided. This requires a great deal of study to make sure it will split
along certain natural lines. A narrow notch is then cut with another diamond having a sharp point. An
iron or steel edge is laid on this line and a sharp blow is struck. If all
has been done correctly, the diamond splits instantly in two in
exactly the direction desired.
Diamonds also have 'facets', or little faces, cut into them.
This is done on a high-speed iron wheel on the edge of which is
diamond dust mixed in oil. The average brilliant diamond is
cut with 58 facets. All this is done to give the diamond the right
shape and brilliance.
Basically, a diamond is a beautiful gem. Its beauty makes
it desirable and valuable. The value of one diamond differs
from that of another. That is because they vary considerably
in colour and quality. They occur in all colors of the rainbow.
Some colors are rarer than others. The highest values are
placed on those tinged with red or blue, and clear, colorless
diamonds. Another factor which determines its value is purity.
Diamonds may be as pure as a drop of water, or may show defects
from a small pinpoint to a large flaw.
There are many diamonds that have been so valuable they have actually played a part in history.
Possession of the famous Koh-i-noor (Mount of Light) was so greatly desired by the rulers of Asia
that practically all of the conquests of India from 1400 to 1828 were the result of it. The Hope, an
unusually blue diamond weighing about 44 carats, has also passed through many hands. The Hope is
said to bring misfortune to all who possess it.
Inferior grade diamonds are used in industry. Many are manufactured into diamond-grinding
wheels which are used to sharpen tools and to grind lenses. Industrial diamonds are also used in
drills by mining companies to drill through rock.
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1. |
Which of the following statements about diamonds is true ? |
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(A) |
They were 'squeezed together' by scientists. |
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(B) |
They are millions of years old.
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(C) |
They were formed when the earth was cold. |
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(D) |
They were combined with highly crystallized carbon. |
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2. |
A diamond is unique because |
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(A) |
it is the hardest substance on earth.
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(B) |
it is as hard as other hard substances. |
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(C) |
it is used for jewelry. |
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(D) |
it is not easy to make it into jewelry. |
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3. |
From the third paragraph, we know that |
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(A) |
dividing a diamond is a difficult, time consuming task.
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(B) |
a diamond has natural lines that divide it into equal halves. |
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(C) |
a diamond is gently cut with an iron or steel edge. |
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(D) |
a diamond with a sharp point is easily divided according to
specifications. |
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4. |
In the passage, the word instantly means |
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(A) |
equally. |
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(B) |
immediately.
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(C) |
carefully. |
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(D) |
almost. |
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5. |
Diamonds which are less valuable are those that are |
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(A) |
tinged with red. |
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(B) |
colorless |
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(C) |
very pure. |
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(D) |
flawed.
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6. |
Which of the following statements about The
Hope is not true ? |
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(A) |
It is very valuable. |
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(B) |
It is beautiful and large. |
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(C) |
It has changed owners many times. |
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(D) |
It brings luck to its owner.
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7. |
Diamonds are used for the following purposes
except |
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(A) |
as jewelry. |
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(B) |
as tools for cutting other diamonds. |
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(C) |
as rewards for conquering countries.
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(D) |
in the manufacture of industrial tools. |
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8. |
Which would be the most suitable title for
this passage ? |
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(A) |
The History of Diamonds |
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(B) |
Processing Diamonds Into Jewelry |
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(C) |
Nature's Hardest Substance
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(D) |
Famous Diamonds of the World |
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9. |
Why does a diamond have 'facets' cut into it
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10. |
Name two factors which determine the value
of a diamond. |
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Sponsored Links
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Answers : 1) B 2) A
3) A 4) B 5) D
6) D 7) C 8) C 9) It
has 'facets' cut into it to make it have the right shape and brilliance.
10) The two factors are its color and quality or purity. |
