Estimation of refractive index


The difference between the refractive indices of the medium and the mineral can be estimated from the relief. As the refractive index of the medium is known, we can calculate the difference in the refractive index of the mineral.

In the images that follow, the medium is Canada Balsam with N = 1.54, and it is assumed that all the mineral grains have higher indices than that of the cement.

By pressing the links you can observe mineral grains with refractive indices ranging between the margins indicated.

1,50 - 1,60

1,60 - 1,70

1,70 - 1,80

1,80 - 1,90

1,90 - 2,00

> 2,00


In the previous screen, we saw grains whose indices varied by a tenth. However, these can be even more accurately defined, especially on the low scale indices (similar to the balsam they are in). Here we have a series of minerals which correspond to the indices which the buttons show.

n = 1,54

n = 1,56

n = 1,58

n = 1,60



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