MINERAL MIDTERM Flashcards
(46 cards)
1
Q

A
- Pyrite
- FeS2
- Streak is greenish-black
- Conchoidal fracture
- Hardness 6-6.5
- SG is approx 5.1 (heavier than most emtallic minerals)
2
Q

A
- Marcasite
- FeS2
- Streak is greenish to brownish-black
- Sometimes a faintly decectable sulfur smell
- Color is brassy yellow with a greenish tint
- multi-color tarnish may be present
3
Q
Pyrrohotite
A
- Fe(1-x)S (x=0 to 0.2)
- Color is bronze
- Luster is metallic
- Hardness is 3.5 - 4.5
- Streak is grey-black
- Weakly magnetic
4
Q
Covellite
A
- Covellite
- CuS
- Color is deep metallic indigo blue (tarnished purple-black) w/ irridescent flashes of yellow and red
- Cleavage is perfect in one direction forming thin, flexible sheets
- Fracture is flaky
- Hardness is 1.5 - 2
- SG is 4.6 - 4.8
- Streak is grey to black
5
Q
Chalcocite
A
- Cu2S
- Chalcocite
- Color is dark grey to black
- Xtals are usually deeply grooved/striated
- Cleavage is perfect in 2 directions, prismatically
- Fracture is conchoidal
- Hardness is 2.5 - 3
- Streak is shiny black to grey
6
Q

A
- Chalcopyrite
- CuFeS2
- Color is brassy yellow, tarnishes to irridescent blues, greens, yellows, and purples
- Cleavage is rather poor in 1 direction
- Hardness is 3.5 - 4
- Streak is dark green
7
Q

A
- Bornite
- Cu5FeS4
- Color is brown to black with a typical purplish-bluish tarnish, a reddish bronze color on freshly broken surfaces
- Cleavage is very poor
- Fracture is conchoidal
- Hardness is 3
- Streak is grey-black
8
Q

A
- Sphalerite
- (Zn, Fe)S
- Color is typically black but can be brown, yellow, reddish, green, and less commonly white or colorless
- Luster is adamantine or resinous or submetallic to earthy
- Cleavage is perfect in 6 directions forming dodecahedrons
- Fracture is conchoidal but rarely seen
- Hardness 3.5 - 4
- Streak is yellow to light brown
- triboluminescence
- Pyroelectric

9
Q

A
- Galena
- PbS
- Color is lead to silver grey sometimes with a bluish tint
- Habits include cubes, octahedron, and combos
- Cleavage is perfect in 4 directions
- Fracture is uneven
- Hardness 2.5+
- SG is 7.5+ (especially heavy)
- Streak is lead grey
10
Q

A
- Cinnabar
- HgS
- Color is bright scarlet or cinnamon red to a brick red
- Luster is adamantine to submetallic
- Hardness is 2 - 2.5
- SG is 8.1+ (especially heavy for non-metallic mineral)
- Habits are rarely individual xtal, commonly crusts and massive

11
Q

A
- Realgar
- As4S4
- Color is orange to red
- Luster is resinous, adamantine, to submetallic
- Cleavage is good in 1 direction
- Hardness is 1.5 - 2
- Streak is orange-yellow
- Unstable in light
- Almost always inclue orpiment

12
Q

A
- Orpiment
- As2S3
- Color is orange-yellow to yellow
- Hardness is 1.5 - 2
- Streak is yellow
- Unstable in light
- Distinct odor similar to sulfur but due to the aresenic
13
Q

A
- Stibnite
- Sb2S3
- Color is steel grey to silver
- Luster is metallic
- Cleavage is perfect in lengthwise direction
- Streak is dark grey
- Striated lengthwise
- Slightly flexible xtals

14
Q

A
- Molybdenite
- MoS2
- Color is silver metallic with a bluish cast
- Luster is metallic
- Cleavage is perfect in 1 direction, forming sheets
- Fracture is flaky
- Hardness is 1.5 - 2
- Streak is bluish grey

15
Q

A
- Arsenopyrite
- FeAsS
- Color is brassy white to grey
- Luster is metallic
- Hardness is 5.5 - 6
- SG is approx 6.1 (slightly heavier than usual)
- Bitter smell when powdered or broken

16
Q

A
- Tetrahedrite
- (Cu, Fe)12Sb4S13
- Color is black to steel grey to silver
- Luster is metallic
- No cleavage
- Fracture is conchoidal
- Hardness is 3 - 4+
- Tarnishes to greenish shade
17
Q

A
- Kernite
- Na2B4O6(OH)2 3H2O
- Color is colorless to white
- Luster is vitreous to pearly
- Cleavage is perfect in 2 directions
- Fracture is splintery due to cleavage
- SG is 1.9 (very low density)
- Streak is white

18
Q

A
- Borax
- Na2[B4O5(OH)4] 8H2O
- Color is white
- Luster is dull/earthy
- Cleavage is perfect in 1 direction
- Fracture is conchoidal
- Hardness is 2 - 2.5
- SG is 1.7 (very light density)
- Streak is white
- Sweet alkaline taste
19
Q

A
- Gold
- Au
- Streak is golden yellow
- SG is 19.3+ (very heavy)
- Ductile, sectile, and malleable
- Native element

20
Q

A
- Silver
- Ag
- Streak is silver white
- Hardness is 2.5 - 3
- Ductile, sectile, malleable
- Native element

21
Q

A
- Copper
- Cu
- Native element
- Streak is reddish copper
- Ductile, sectile, malleable

22
Q

A
- Sulfur
- S
- Native element
- Cleavage is poor in 2 directions
- Odor
- Poor heat conductivity
- Massive or powdery habits

23
Q

A
- Diamond
- C
- Native element
- Color is variable, tends toward pale yellow and brown
- Luster is adamantine to waxy
- Hardness is 10
- Cleavage is perfect in 4 directions
- Streak is white

24
Q

A
- Graphite
- C
- Native element
- Habit includes massve lamellar veins and earthy masses
- Cleavage is perfect in 1 direction
- Thin flakes are flexible but inelastic

25

* Halite
* Habit is predominantly cubes
* Cleavage is perfect in 3 directions forming cubes
* Fracture is conchoidal
* SG is 2.1 (light)
* Hardness is 2
* Salty taste

26

* Sylvite
* Cleavage is good in 3 directions
* Hardness is 2 - 2.5
* SG is 3.9 - 4.1 (heavier than average for translucent)
* Dissolves easily in water
* Bitter taste
* Does not powder easily

27

* Fluorite
* Cleavage is eprfect in 4 directions forming octahedrons
* Fracture is irregular and brittle
* Hardness is 4
* Often fluoresces
* Color zoning

28

* Corundum
* Al2O3
* Luster adamantine to vitreous
* All colors
* Parting occurs in 3 directions
* Hardness 9
* Streak is white
* EXTREME hardness
29

* Fe2O3
* Color is metallic grey, dull to bright red
* Parting in 2 directions
* Hardness is 5 - 6
* SG is 5.3 (slightly above)
* Streak is red\*\*\*\*\*\*

30

* Ilmenite
* FeTiO3
* Color is iron black, grey w/brownish tint
* Hardness is 5 - 6
* Streak is black
* No cleavage

31

* Spinel
* All colors
* Luster is vitreous
* No Cleavage
* Conchoidal fracture
* Hardness is 7.5 - 8
* SG is 3.6 - 4
* Streak is white

32

* Magnetite
* Color is black, grey w/brownish tint
* Streak is black
* Magnetism
* Hardness is 5.5 - 6.5
* Lodestone is permenently magnetized

33

* Chromite
* Color is black to brownish black
* No cleavage
* Hardness is 5.5
* Streak is grey
* Weakly magnetic
34

* Rutile
* Good cleavage in 2 directions
* Hardness is 6 - 6.5
* SG is 4.2 (slightly heavy)
* Streak is bright to dark red
* Sprarkles higher than diamond
35

* Pyrolusite
* Color is darkish, black to lighter grey, sometimes bluish
* Cleavage is good in 2 directions forming prisms, rarely seen
* Streak is bluish-black
* Hardness 2 - 6 (xtal)
36

* Cuprite
* Color is dark red to almost black
* Luster is adamantine, submetallic, earthy
* Cleavage is fair in 4 directions forming octahedrons
* Hardness is 3.5 - 4
* Streak is shiny metallic brownish-red

37

* Gibbsite
* Color is bluish, greenish-white, grey-white
* Luster is vitreous - pearly
* Hardness is 2.5 - 3.5
* Streak is white
* Clay-smell\*\*\*\*\*

38

* Goethite
* Color is yellowish to reddish to dark brown
* Luster is adamantine to dull
* Cleavage is perfect in 1 direction
* Uneven + splintery fracture
* Hardness is 5
* Streak is brownish, brownish-yellow to orange-yellow

39

* Limonite
* Various shades of brown + yellow
* Luster is earthy
* massive, layered, botryoidal, and stalactitic
* Fractureis crumbly to earthy
* Hardness is 4
* Streak is yellowish-brown
* LACKS xtals forms

40

* Calcite
* Colorless/white, grey, yellow, green
* Luster is vitreous
* Habit is extremely variable
* Hardness is 3
* Streak is white
* Refractive properties...optical

41

* Aragonite
* White, red, yellow, orange, green, blue, + brown
* Luster is dull to vitreous
* Hardness is 3.5 - 4
* Streak is white
* SG is slightly heavier than calcite
* Effervesces in cold HCl
42

* Siderite
* Pale, yellow-tannish, grey, brown, red, black, and colorless
* Luster is vitreous
* Cleavage is perfect in 3 directions
* SG is 3.9 (relatively heavy)
* Streak is white
* Magnetic when heated

43

* Rhodochrosite
* Pink, rose-red, cherry-red, yellow-grey
* Luster is vitreous to pearly
* Streak is white

44

* Dolomite
* Color is white, grey, pink
* Luster is vitreous to pearly
* Habit... saddle-shaped rhombohedral twins, also slightly curved faces
* Hardness is 3.5
* Streak is white
* Effervesces weakly w/ warm HCl after powdered

45

* Malachite
* Bright green, dark green
* Luster is dull to vitreous
* Botryoidal, stalactitic , globular
* Fracture is conchoidal to splintery
* Streak is light green

46

* Azurite
* Azure-blue
* Luster is dull to viitreous
* Streak is light blue
