CRYSTALS IDENTIFICATION

Question 1

what are the key mineral identifications

Answer 1

• colour
• streak colour
• hardness
• cleavage
• fracture
• lustre
• transparency
• habit
• magnetism
• radioactivity
• mineral arrangement

Question 2

key mineral identification: streak colour

Answer 2

colour of a mineral in powdered form.

usually obtained by rubbing mineral on a hard, white surface, such tile of unglazed porcelain

Question 3

key mineral identification: hardness

Answer 3

resistance to abrasion

measuring depth of rock penetration or size of impression left by rock

scales used is ‘Mohs hardness scale’

Question 4

key mineral identification: cleavage/ fracture

Answer 4

-c
break of mineral along definite planes related to internal atomic structure(smooth plane). signi

-f
irregular break bearing no relationship to crystal structure(ruff)

Question 5

key mineral identification: lustre/types

Answer 5

quality of light reflected from surface of mineral

metallic

non-metallic:

• silky
• vitreous(glassy)
• dull

Question 6

key mineral identification: transparency/types

Answer 6

ability of mineral to transmit light

transparent
translucent
opaque

Question 7

What do you call internal atomic structure of cystals

Answer 7

crystal lattice

Question 8

key mineral identification: habit

Answer 8

refers to shape/ state of aggregation

Question 9

key mineral identification: what gives crystal their hardness

Answer 9

mineral arrangement/type of bond between atoms of crystal

Question 10

key mineral identification: strongest to weakest chemical bond

Answer 10

covalent bond > ionic bond > hydrogen bond > Van der Waals forces