Optical Mineralogy

Question 1

What happens when a polarized light microscope is used?

Answer 1

When in use, light passes through a sample ad interacts with the internal structures of mineral grains. When it emerges from a sample, it has been altered due to interactions within the mineral grain.

Question 2

Thin section

Answer 2

Slabs of rock glued to a glass slide

Question 3

Isotropic

Answer 3

Optical properties of mineral which are the same independent of the orientation.
All the mineral’s physical properties are the same at any point

Question 4

Anisotropic

Answer 4

Properties of mineral are not the same at all points or directions but may vary continuously with changing direction of observation.

Eg. Diff absorption of light, diff refractive indexes