Mineralogy and Petrology

Question 1

Name 3 alluminosilicates

Answer 1

kyanite, andalusite and sillimanite

Question 2

Forsterite and Fayalite are in what mineral group?

Answer 2

Olivines

Question 3

The 2 main isolated orthosilicates?

Answer 3

Olivine and garnet

Question 4

The 2 single chain inosilicates?

Answer 4

Orthopyroxene and Clinopyroxene

Question 5

What ranges the orthopyroxenes

Answer 5

Ensatite to ferrisolite

Question 6

Extinction angle of OPX’s

Answer 6

0

Question 7

Extinction angle of CPX’s

Answer 7

30 to 60

Question 8

Enstatite, Ferrosilite are what?

Answer 8

Orthopyroxenes

Question 9

Chemical formula for Enstatite?

Answer 9

Mg2Si2O6 or Mg2SiO3

Question 10

Chemical formula for Ferrosilite?

Answer 10

Fe2Si2O6 or Fe2SiO3

Question 11

Diopside and Hedenbergite are what?

Answer 11

Clinopyroxenes

Question 12

Chemical formula for Diopside?

Answer 12

CaMgSi2O6

Question 13

Chemical formula for Hedenbergite?

Answer 13

CaFe2+Si2O6

Question 14

Describe an Eclogite

Answer 14

Metamorphic rock containing garnets and pyroxenes

Question 15

How are double chain tetrahedra formed?

Answer 15

If two single chain tetrahedra can share three of their oxygens

Question 16

What mineral group is Amphibole?

Answer 16

Double chain - Inosilicate

Question 17

Name 4 amphiboles

Answer 17

Hornblende, anthophyllite, tremolite and pargasite

Question 18

What is the general formula for amphiboles??

Answer 18

AB2C5T8O22W2 or replace W with OH2

Question 19

What mineral group has variable coordination numbers??

Answer 19

Amphibole

Question 20

Anthophillites mineral formula??

Answer 20

Mg2Mg5Si8O22(OH)2

Question 21

Mineral group for cummingtonite?

Answer 21

Amphibole

Question 22

For a sheet silicate, what is the tetrahedral part?

Answer 22

(Si2O5)2-

Question 23

For a sheet silicate, what is the octahedral part?

Answer 23

Mg(OH)2, Mg3(OH)6 or Mg3(OH)3(OH)3

Question 24

Name the hydroxide mineral made of sheets of octrahedra

Answer 24

Brucite

Question 25

Kaolinite and talc are what type of minerals?

Answer 25

Clay

Question 26

Muscovite and Paragonite are what type of micas?

Answer 26

Di-octahedral

Question 27

Phlogopite and Biotite are what type of micas??

Answer 27

Tri-octahedral

Question 28

What are Miller Indices?

Answer 28

(h,k,l) = point (hkl) = plane [hkl] = direction

Question 29

A layer of brucite and a layer of talc make up what?

Answer 29

Chlorite

Question 30

Formula for coesite?

Answer 30

SiO2

Question 31

What formula makes the basic feldspar ring?

Answer 31

4 x SiO2

Question 32

4 oxide structures

Answer 32

Halite, Rutile, Corundum and Spinel

Question 33

What are garnets coordination numbers??

Answer 33

A site (Mg, Mn, Ca and Fe2+)3 = 8,
M site is Al2 = 6 and Si3 = 4

Question 34

Pyrope’s coordination numbers?

Answer 34

Mg3 = 8, Al2 = 6 and Si3 = 4

Question 35

Plagioclase and spinel are what rich phases at low pressures?

Answer 35

Aluminium

Question 36

What do pyroxenes dissolve into at depth??

Answer 36

Garnet

Question 37

What are the other two phases of Olivine? What pressures do they form at??

Answer 37

Wadsleyite = 13-14Gpa
Ringwoodite = 18Gpa

Question 38

Formula for diopside?

Answer 38

CaMgSi2O6

Question 39

What is the end member for feldspars?

Answer 39

AlSi3O8

Question 40

Order of Bowen’s reaction series?

Answer 40

Olivine-Pyroxene-Amphibole-Biotite mica-Orthoclase feldspar-Muscovite mica-Quartz

Calcium - Sodium rich fledspars

Question 41

Definition of eutectic

Answer 41

Batch or crystallization produces the same final product. Lowest melting point in the system

Question 42

What is the pyroxene end member

Answer 42

Si2O6

Question 43

Enstatite formula

Answer 43

Mg2Si2O6