F1 - Elements, Minerals and Rocks

Question 1

What is an Element?

Answer 1

A substance made from one type of atom

Question 2

In order of abundance, what are the 8 main elements in the Earth’s crust?

Answer 2

Oxygen O
Silicon Si
Aluminium Al
Iron Fe
Calcium Ca
Sodium Na
Potassium K
Magnesium Mg

Question 3

What is an Atmophile?

Answer 3

‘Gas loving’
Volatile elements in liquids and gases
Found in the Atmosphere and Hydrosphere

Question 4

What is a Chalcophile?

Answer 4

‘Ore loving’
Elements that combine well with sulphur
Found in the Crust and Upper Mantle

Question 5

What is a Lithophile?

Answer 5

‘Rock loving’
Elements that combine well with oxygen
Found in the Crust and Mantle

Question 6

What is a Siderophile?

Answer 6

‘Iron loving’
Elements typical of the Core

Question 7

What is a Mineral?

Answer 7

Naturally occurring, inorganic, chemical compounds or elements with compositions that can be expressed as chemical formulae

Question 8

Shape

Answer 8

Amorphous - No shape

Question 9

Colour

Question 10

Cleavage - plane of weakness in a mineral along which it tends to split

Answer 10

Without - Quartz - N/A
One direction - Muscotive - 180
Two directions - Feldspar - 90
Two directions - Hornblende - 60/120
Three directions - Halite - 90
Three directions - Calcite - 60/120

Perfect/Good - Split easily along cleavage - less likely to fracture
Poor/None - tend to fracture

Question 11

Fracture - how the mineral breaks

Answer 11

Uneven
Conchoidal

Question 12

Streak

Answer 12

The mineral in powered form
Done on streak plate

Question 13

Lustre

Answer 13

The way light is reflected form the surface of the mineral
Pearly/Silky
Vitreous
Metallic
Dull

Question 14

Reaction to HCl

Answer 14

Only Calcite will react
It will fizzle/bubble

Question 15

Hardness

Answer 15

Finger nail - 2.5
Copper Penny - 3.5
Steel pin - 4.5

Question 16

Relative density

Answer 16

Heft test
Heavy for size - High density
Weight for size - Medium density
Lighter for size - Low density

Question 17

Euhedral

Answer 17

Well formed crystal shape

Question 18

Subhedral

Answer 18

Partially well formed crystals

Question 19

Anhedral

Answer 19

Amorphous

Question 20

Thin section

Answer 20

Where the rock is sliced thin, is transparent and can be look at through a scope

Question 21

Rock forming minerals

Answer 21

Rock - is a aggregate or mixture of one or more minerals
Most are based on Silicate minerals (SiO4)
The rest are limestones based on calcium carbonate/calcite
And some minor evaporates (rock salt/Halite) - these are not classed as rock forming

Question 22

Silica Tetrahedra

Answer 22

Silicates form bulk of crust and virtually all the mantle
All silicates are built form the same basic unit cell, the silicon-oxygen tetrahedra
How tight these tetrahedra’s are bonded together controls the hardness and cleavage of the mineral
Silicate minerals have different shapes but are all built from the tetrahedra

Question 23

Isolated tetrahedra

Answer 23

One Si
Four O
No cleavage - Quartz

Question 24

Single chain

Answer 24

Isolated tetrahedra’s link up and share one O between each of them and make a chain
Two Si
Seven O - if looking at two of them
Cleavage at 90* - Augite (triangle)

Question 25

Double chain

Answer 25

Two chains link up and share one oxygen between each link
Four Si
Thirteen O - looking at four
Cleavage at 60-120 - Hornblende (square)

Question 26

Sheet

Answer 26

Perfect cleavage - Mica (b+m), Clay minerals, Talc

Question 27

Framework