native elements

Question 1

gold crystal form

Answer 1

• isometric, octahedral crystals
• arborescent
• irregular, filliform, reticulated, dendritic
• irregular plates scales or masses
• rounded or flattened grains “nuggets”

Question 2

gold cleavage

Answer 2

none. hackly fracture

Question 3

gold hardness

Answer 3

2.5 to 3. malleable sectile

Question 4

gold specific gravity

Answer 4

19.3 pure
15 impure with other metals

Question 5

gold color

Answer 5

shades of yellow, paler with silver, metallic opaque

Question 6

gold occurrence

Answer 6

1. hydrothermal quartz veins (vv fine grained)
2. placer deposits, conglomerates, detrital grains “nuggets”

Question 7

gold remarks

Answer 7

• color, malleability and sectility

Question 8

gold vs pyrite

gold vs chalcopyrite

Answer 8

pyrite is harder

chalcopyrite is brittle

Question 9

silver crystal form

Answer 9

• isometric, malformed
• branching aborescent, reticulated groups
• in coarse or fine wire
• irregular masses, plates and scales

Question 10

silver cleavage

Answer 10

none. hackly fracture

Question 11

silver hardness

Answer 11

2.5 to 3. malleable and ductile

Question 12

silver specific gravity

Answer 12

10.5 pure
10-12 impure

Question 13

silver color

Answer 13

metallic opaque. silver white, tarnished brown to gray black

streak silver white

Question 14

silver occurrence

Answer 14

large deposits from hydrothermal solution precipitates

in smaller amounts oxidized portions of ore deposits

Question 15

silver remarks

Answer 15

• color, malleability and specific gravity

Question 16

copper crystal form

Answer 16

• isometric, tetrahexahedral, cube, dodecahedral, octahedral, malformed branching and aborescent
• irregular masses plates and scales
• twisted and wirelike

Question 17

copper cleavage

Answer 17

none. hackly fracture

Question 18

copper hardness

Answer 18

2.5 to 3. ductile and malleable

Question 19

copper specific gravity

Answer 19

8.9

Question 20

copper color

Answer 20

dull luster, copper red, tarnish to dark

Question 21

copper occurrence

Answer 21

• primary deposits associated with basaltic lavas, the copper is deposited through reaction of hydrothermal fluids with iron oxide minerals
• smaller amounts in oxidized zones of copper deposits associated with malachite azurite and cuprite

Question 22

copper remarks

Answer 22

• copper red, malleability, high specific gravity hackly

Question 23

sulfur crystal form

Answer 23

• orthorhombic, pyramidal, 2 dipyramids
• prism 011 and base
• masses perfectly crystallized
• massive reniform stalactitic incrustations

Question 24

sulfur cleavage

Answer 24

none. conchoidal fracture to uneven. brittle

Question 25

sulfur hardness

Answer 25

1.5 to 2.5

Question 26

sulfur specific gravity

Answer 26

2.05 to 2.09

Question 27

sulfur color

Answer 27

resinous. transparent to translucent. sulfur yellow. impure shades of green gray red

Question 28

sulfur occurrence

Answer 28

- crater rims of extinct volcanoes as gas deposits - veins with metallic sulfides from oxidation of sulfides - in tertiary sedimentary rocks assoc. with anhydrite gypsum and limestone - assoc with celestite, gypsum calcite and aragonite

Question 29

sulfur remarks

Answer 29

- poor heat conductor - cracks bc hear from hand expands the outside layers - yellow color

Question 30

diamond crystal form

Answer 30

- isometric, octahedral, cubes and dodecahedrons - octahedral often has curved faces - twins on 111

Question 31

variety of diamond that has a rounded form and rough exterior resulting from radial or cryptocrystalline aggregate

Answer 31

bort

Question 32

applies to badly colored or flawed diamonds without gem value

Answer 32

bort

Question 33

diamond cleavage

Answer 33

octahedral 111 perfect

Question 34

diamond hardness

Answer 34

10

Question 35

diamond specific gravity

Answer 35

3.51

Question 36

diamond color

Answer 36

adamantine. uncut greasy. colorless pale yellow. shades of red orange green blue brown. deeper shades are rare noncleavable, opaque, less brittle than crystals???

Question 37

a black or grayish black bort

Answer 37

carbonado / carbon

Question 38

diamond occurrence

Answer 38

- primary: in kimberlites as intrusive bodies, commonly circular with pipelike shape aka diamond pipes - also in alluvial deposits (placers), bc of their inert nature, great hardness and high specific gravity

Question 39

diamond remarks

Answer 39

- great hardness, adamantine, cleavage

Question 40

graphite crystal form

Answer 40

- tabular crystals with hexagonal outline - prominent basal face - foliated or scaly masses - radiated or granular

Question 41

graphite cleavage

Answer 41

basal perfect 0001. flexible folia, not elastic

Question 42

graphite hardness

Answer 42

1-2

Question 43

graphite specific gravity

Answer 43

2.23

Question 44

graphite color

Answer 44

metallic sometimes greasy. black black streak

Question 45

graphite occurrence

Answer 45

- in metamorphic rocks: crystalline limestone, schists and gneiss - hydrothermal veins associated with quartz, orthoclase, tourmaline, apatite, pyrite and titanite - also original constituent in some igneous rocks

Question 46

graphite remarks

Answer 46

- black, foliated, extreme softness, greasy

Question 47

molybdenite vs graphite

Answer 47

moly has blue tone graphite is black