Unlike spinel, taaffeite displays the property of double refraction that allows distinction between these two minerals.
12.
This is due to double refraction as the light bends twice, when entering and leaving the prism.
13.
This Maltese cross is because of its liquid-crystalline structure giving it a double refraction ( birefringence ).
14.
With this double refraction, the two subsidiary images appear as one above and one below the main image.
15.
He studied reflection was published in 1809 and his theory of double refraction of light in crystals, in 1810.
16.
A quartz wedge also may be calibrated by determining the amount of double refraction in all parts of its length.
17.
As the exact nature of the double refraction varies for different crystal structures, phase contrast aids in the identification of minerals.
18.
Amicite is classified as biaxial anisotropic so the velocity of light varies depending on direction through the mineral, as well as showing double refraction.
19.
Huygens had experimented in 1672 with double refraction ( birefringence ) in Icelandic spar ( calcite ), a phenomenon discovered in 1669 by Rasmus Bartholin.
20.
Anisotropic crystals have double refraction of light where light of different polarizations is bent different amounts by the crystal, and therefore follows different paths through the crystal.
