List of top Geology Questions on Crystallography

In the isometric system, the difference in the number of symmetry planes in class $4_3m(Hexahedral) class and 2/m3$ (Diploidal) is .......... (In integer)

Which of the following statements are true for ionic bonding?
A. Halite is formed by ionic bonding,
B. Diamond is hardest mineral because of strongest ionic bonding,
C. No molecules are formed by ionic bonding,
D. Minerals with ionic bonding have high melting points and are mechanically hard and strong. Choose the correct answer from the options given below:

Which of the following statements are true for the optically isotropic minerals?
A. They are opaque,
B. Light is transmitted with the same velocity in all directions through them,
C. Refractive index varies with direction of transmission of light,
D. Garnet is an optically isotropic mineral. Choose the correct answer from the options given below:

Which of the following statements is/are true for the Bowen's Reaction Series?
A. It is related to comparative destruction of rocks against applied stresses,
B. It is related to change in animal behaviour in response to change in climate,
C. It is related to crystallisation of minerals from the cooling magma,
D. It contains a continuous and a discontinuous series. Choose the correct answer from the options given below:

Which of the following statements is/are true for hemihedral forms?
A. They belong to the same crystal class as the holohedral forms,
B. They have the same indices as the holohedral form,
C. They have half number of faces as the holohedral form,
D. For each holohedral form these correspond to two hemihedral forms. Choose the correct answer from the options given below:

Arrange the following in which they appear with decreasing temperature:
A. Tridymite,
B. Cristobalite,
C. Low quartz,
D. High quartz. Choose the correct answer from the options given below:

Given below are two statements:
Assertion (A): The angle between any two faces of a crystal is termed as interfacial angle.
Reason (R): The interfacial angles of corresponding faces of different crystals are constant if they have same chemical composition and measurements are taken at same temperature.

Given below are two statements:
Assertion (A): Gypsum has lower density than anhydrite.
Reason (R): Hydrated minerals tend to expand many times the original volume of the anhydrous minerals.

Given below are two statements:
Assertion (A): In a hand specimen quartz can be easily distinguished from orthoclase.
Reason (R): Orthoclase has lower refractive index than quartz.

The rhombohedron has:

Which of the following is not a diagnostic mineral property?

Which of the following group of minerals shows highest number of polymorphs?

The relative size and shape of a particular face of a crystal is a function of:

The maximum amount of substitution of Al for Si is found in:

Purple colour of Amethyst is due to the presence of:

Lustre is defined as the appearance of a mineral in:

Which of the following forms of silica is pseudo-isometric?

A solid crystal in which a face on one side is opposite to a point on the other, is called:

Which of the following pairs do not have the same number of classes in their crystal system?

Zircon type crystals may be designated as having: