Exploring for Diamonds (Chapter 5, Key Terms & Key Concepts)

Question 1

A deposit where gems are
eroded from their source rock, then transported away from the source and further
concentrate

Answer 1

Aluvial deposit

Question 2

Large-scale character
sampling.

Answer 2

Bulk sampling

Question 3

Testing for the size,
shape, clarity, and color of the diamonds in
a deposit.

Answer 3

Character sampling

Question 4

Diamond rough with good
enough size, shape, clarity, and color to
produce a polished stone suitable for use
in jewelry.

Answer 4

Cuttable rough

Question 5

Separating heavier
materials (diamonds) from a test sample.

Answer 5

Gravity sorting

Question 6

Minerals formed
together with diamonds at great depths
and brought to the surface by the same
kimberlites or lamproites.

Answer 6

Indicator minerals

Question 7

Diamond rough suitable
for use in tools, drills, abrasives, and other
industrial applications.

Answer 7

Industrial rough

Question 8

Secondary diamond
deposit carried by rivers or streams to the
ocean floor or shoreline.

Answer 8

Marine deposit

Question 9

Screening for the
presence of tiny diamonds in a sample.

Answer 9

Microdiamond testing

Question 10

Concentration of diamond in a
potentially mineable deposit.

Answer 10

Ore grade

Question 11

Gems found in the rock
that carried them to the surface.

Answer 11

Primary deposit

Question 12

Gems found away
from their primary source.

Answer 12

Secondary deposit

Question 13

Growing diamond demand helps motivate the
search for new diamond sources.

Answer 13

Key Concept

Question 14

It takes many years and millions of dollars to
develop a diamond mine.

Answer 14

Key Concept

Question 15

Modern diamond exploration involves careful
planning and sophisticated equipment.

Answer 15

Key Concept

Question 16

For a mine to be successful, the projected value
of its diamonds must be more than the cost of
mining them.

Answer 16

Key Concept

Question 17

Diamond exploration specialists start by looking
for the oldest parts of the earth’s crust.

Answer 17

Key Concept

Question 18

Most diamonds mined today come from pipes.

Answer 18

Key Concept

Question 19

A mining company must consider a potential
mine’s location, climate, and political conditions
along with its content.

Answer 19

Key Concept

Question 20

Only a small percentage of known diamond deposits are mined because most

Answer 20

are not profitable.

Question 21

Diamonds classified as cuttable can be 100 times more valuable than

Answer 21

industrial diamonds.

Question 22

Most of the diamonds mined today come from

Answer 22

pipes.

Question 23

Indicator minerals in kimberlite and lamproite include tiny

Answer 23

diamonds

Question 24

Gravity sorting separates diamonds from

Answer 24

lighter materials.

Question 25

A mine’s potential profitability depends in part on

Answer 25

its ore grade.

Question 26

For more than 2,000 years, the only known diamond sources were

Answer 26

alluvial.

Question 27

The first step in exploring for diamonds is to

Answer 27

look for the oldest parts of the earth’s crust.

Question 28

The concentration of diamonds within a pipe is called

Answer 28

ore grade.

Question 29

A profitable mine

Answer 29

produces diamonds whose value is higher than the mine’s operating costs.

Question 30

Diamond rough suitable for use in tools, drills, and abrasives is

Answer 30

industrial quality.

Question 31

Diamond rough suitable for use in jewelry is called

Answer 31

cuttable.

Question 32

Diamond deposits found at the ocean’s shore are

Answer 32

marine deposits.

Question 33

Diamonds are more concentrated in

Answer 33

marine deposits.

Question 34

To focus their search for diamond deposits, geologists look for

Answer 34

indicator minerals.