Dispersion in gemology

In the abstruse analogue of gemology, burning is the aberration in the refractive basis of a actual at the B and G (686.7 nm and 430.8 nm) or C and F (653.3 nm and 486.1) Fraunhofer wavelengths, and is meant to accurate the amount to which a prism cut from the gemstone shows "fire", or color. Burning is a actual property. Fire depends on the dispersion, the cut angles, the lighting environment, the refractive index, and the viewer.8