topic 1: diagnostic properties of minerals

Question 1

What is lustre?

Answer 1

The way a mineral reflects light off of it’s surface.

Question 2

What are the common types of lustre?

Answer 2

metallic, vitreous (glassy), pearly or dull.

Question 3

What is streak?

Answer 3

The colour of a minerals powder.

Question 4

How do you test for streak?

Answer 4

Rubbing a mineral specimen on an unglazed white porcelain tile.

Question 5

What are the two possible results of streak test?

Answer 5

Will leave behind a powdery streak or will scratch the tile.

Question 6

What is hardness?

Answer 6

Resistance of a mineral to being scratched and is measured on Mohs scale.

Question 7

How hard is a mineral if it can be scratched by a fingernail?

Answer 7

< 2.5

Question 8

How hard is a mineral if it can be scratched by a penny?

Answer 8

< 3.5

Question 9

How hard is a mineral if it can be scratched by a nail?

Answer 9

< 5.5

Question 10

How hard is a mineral if it cannot be scratched by a nail?

Answer 10

over 5.5

Question 11

How hard is a mineral if it can scratch glass?

Answer 11

above 6.5

Question 12

What is cleavage?

Answer 12

The way a mineral breaks or splits when under pressure.

Question 13

What is it called when a mineral with no cleavage breaks?

Answer 13

Fracture.

Question 14

Give an example of a mineral with no cleavage.

Answer 14

Quartz.