Glass optical flint

Thallium oxide is used in manufacturing high coefficient of refraction optical glass (thallium flint glass). Also, the oxide is used to make synthetic gems. 

USE In the separation of plutonium from fission products mamif of optical flint glass,... 

Fig. 11. Index of refraction vs dispersion and optical classification of glasses. The shaded area indicates the region of glass formation. BaF = barium flint BaK = barium crown BaLF = light barium flint BaSF = heavy barium flint BK = borosilicate crown F = flint FK = fluorcrown K = crown ...

FIG. 19-13 Optical separation of mixed glasses separation of flint from colored. (Couiiesy Gunson s Soiiex Ltd.)... 

This soft, silver white metal reacts with air and water. The oxide is applied in optical glasses with high refractive indices (special lenses for powerful cameras and telescopes). Used for special effects in optoelectronics and electronics. Lanthanum exhibits catalytic properties. It is a component of flint and battery electrodes. Lanthanum boride (LaB6) is the superior electron-emitter for electron microscopes. Lanthanum is the first of the series of 14 lanthanides, also called the "rare-earth" metals, whose inner N shells are filled with electrons. They do not belong on the "red list" of endangered species they are neither rare nor threatened with depletion. China is particularly rich in lanthanide ores. 

Crystal, for optical purposes and table-ware, consists of silica or borucio acid, potassa, and more lead than the preceding. In short, it is a simple flint-glass, formed with very pure materials. ... 

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