46
____________ can be used in the preparation of artificial polarizer.
1
Quinine calcium sulphate
2
Lead sulphate
3
Mixture of lead and iodine
4
Quinine iodine sulphate
Answer & Explanation
Answer: Quinine iodine sulphate
47
The chemical composition of sillimanite is
1
Al2O3 Si02
2
AL203 Si02-2H20
3
A1203 2H20
4
A1203 -4H20
Answer & Explanation
48
A biaxial mineral is positive if
1
X is acute bisectrix
2
Z is acute bisectrix
3
Y is acute bisectrix
4
Z is obtuse bisectrix
Answer & Explanation
Answer: Z is acute bisectrix
49
The highest interference colour is produced in a thin section which is
1
parallel to the optic axis
2
perpendicular to the optic axis
3
at an angle of 15° from the cleavage direction
4
at an angle of 45° from the vibration direction
Answer & Explanation
Answer: at an angle of 45° from the vibration direction
50
Which one of the following is a non-pleochroic mineral?
1
Biotite
2
Muscovite
3
Hypersthene
4
Garnet
Answer & Explanation
51
is mineralogically equivalent to granite.
1
Aplite
2
Gabbro
3
Dolerite
4
Syenite
Answer & Explanation
52
is the volcanic equivalent of granodiorite.
1
Rhyolite
2
Dacite
3
Trachyte
4
Phonolite
Answer & Explanation
53
Graphic texture is a product of crystallization at
1
tripple point
2
incongruent point
3
eutectic point
4
quadrotectic point
Answer & Explanation
54
Which of the following may not be of metamorphic origin?
1
Granite
2
Basalt
3
Trachyte
4
Gabbro
Answer & Explanation
55
Ophitic texture is commonly exhibited by
1
lamprophyre
2
dolerite
3
harzburgite
4
trachyte
Answer & Explanation
56
Batholiths are always associated with
1
earthquake zones
2
orogenic belt
3
island arc
4
fold and faults
Answer & Explanation
57
texture is absent in plutonic igneous rocks.
1
Holohyaline
2
Holocrystalline
3
Porphyritic
4
Granitic
Answer & Explanation
58
Conglomerate with compositionally one type of pebble is called
1
polymictic conglomerate
2
oligomictic conglomerate
3
intraformational conglomerate
4
interformational conglomerate
Answer & Explanation
Answer: oligomictic conglomerate
59
Pudding stone is a synonymous term for
1
breccia
2
grit
3
khondalite
4
conglomerate
Answer & Explanation
60
is a light-coloured sandstone with at least 25% feldspar.
1
Orthoquartite
2
Arkose
3
Greywacke
4
Grit
Answer & Explanation
