Also, the low-temperature formation of the spicules, as compared to the high temperature stretching process of commercial fibre optics, allows for the addition of impurities which improve the refractive index.
It can also be used as an optical contact liquid, in conjunction with the gemmological refractometer, for determining the refractive index of certain gemstones.
Since the late 1970s, eye surgeons have been taking advantage of the refractive power of the cornea to correct nearsightedness (myopia) and farsightedness (hyperopia).
