Refractive Index and Becke Line Methods

These flashcards cover key vocabulary related to the lectures on refractive index and Becke line methods in mineral optics.

Refractive Index (RI)

A measure of how much light is refracted or bent when it enters a material.

Becke Line Method

A technique used to determine the refractive index of a mineral fragment by observing the appearance of Becke lines.

Relief

The indication of degree of similarity of RI’s of oil and fragment; higher relief indicates a larger difference between the refractive indices.

Christiansen Effect

The phenomenon in the Becke line method where different illumination colors signify different RI interpretations.

Sodium D line

A specific wavelength of 589.3 nm used for monochromatic illumination in optical measurements.

Dispersion Colors

Colors observed in the Becke line method that arise from differences in refractive indices.

Cargille Laboratories

A company that produces calibrated liquids for refractive index determination.

Refractometer

An instrument used to measure the refractive index of liquids.

Homogeneous Mixture

A mixture in which the composition is uniform throughout, crucial for accurate refractive index matching.

Temperature Coefficient

The rate at which the refractive index of a substance changes with temperature.