List of top Geology Questions on Mineralogy

Which one of the following minerals is NOT formed by chemical weathering?

A metallic mineral weighs 44 g and displaces 11 mL of water when fully immersed. The density of the mineral is ......... g/cc. (In integer)

Which one of the following mineral associations is diagnostic of the highly-oxidized zone of a weathered primary base metal vein?

Match the minerals in Column 1 to their characteristic optical properties in Column 2.

A halide with octahedral cleavage can scratch calcite and can be scratched by quartz. Identify the halide.

Which one of the following minerals does NOT show changes in optical properties upon exposure to UV light?

For a \(2/m\) pyroxene, the extinction angle between the vibration direction and crystallographic axis, X ⊥ c, is 36°. Then the angle Y ⊥ b in degrees will be ............. (In integer)

A metapelite is composed of muscovite + quartz + K-feldspar + kyanite mineral assemblage. If the muscovite and K-feldspar show solid solution between 'Na' and 'K' end-members, the minimum number of components that defines this metapelitic assemblage is ............. (In integer)

A mineral displays magenta interference colour (retardation, \( \Delta m = 550 \, \text{nm} \)) under crossed polarized light. If an accessory plate adds retardation of 100 nm, the interference colour observed is:

Which one of the following minerals has a characteristic pale yellow streak?

Which of the following is a fluorite deposit?

Which one of the following does NOT have a polymorph?

Match the minerals in Group I with their highest order of interference color in Group II (for 0.03 mm mineral thickness).

Group I	Group II
P. Sillimanite	1. First order
Q. Quartz	2. Second order
R. Muscovite	3. Greater than third order
S. Calcite	4. Third order variegated

An orebody contains pyrite and chalcopyrite in the same molar proportions. The percentage concentration of Cu in the ore will be ________. (Round off to the nearest integer) (Use atomic weight, in g/mol, of Cu = 63.55, Fe = 55.85, S = 32.06)

For an anisotropic crystal of thickness 0.04 mm and refractive indices of 1.636 and 1.486 along the slow and fast directions, respectively, the retardation produced is ______ nm. (In integer)

The mole fraction of forsterite in olivine with MgO = 29.17 weight %, FeO = 34.65 weight % and $SiO_2$ = 36.18 weight % is _______ . (Round off to two decimal places) (Use molecular weight, in g/mol, of MgO = 40.31, FeO = 71.85 and $SiO_2$ = 60.00)

The atom percent of Fe in pyrrhotite of composition $Fe_{0.77}S$ is ________. (Round off to two decimal places)

In a mineral with formula $KAl_3Si_3O_{10}(F_{0.5}OH_x)$, the value of ‘x’ is ________ . (Round off to one decimal place)

The value of φ (phi) of a sediment grain having a diameter of 0.125 mm is ______ . (In integer)

Which ones of the following correspond to the Pyroxene group?

Match the minerals in Group I with their highest order of interference color in Group II (for 0.03 mm mineral thickness).

Group I	Group II
P. Bababudan Group	1. Eastern Dharwar
Q. Banded Gneissic Complex-I	2. Western Dharwar
R. Bonai Granite	3. Aravalli
S. Kolar Group	4. Singhbhum

The symbols [100], {100} and (100) in a crystal represent the sequence

The crystal form ‘dome’ contains

Which of the following is an amorphous variety of SiO2?