Cryolite  (Na3AlF6) 

Cryolite Evaporation Material 

Density--- 2.9 g/cm3,   Purity---99.99%

Melting point---1000℃,Vapour pressure at 860℃ 1 Pa, at 925℃ 10 Pa
Properties of thin film
     Transmission range 250 ～ 7000nm
     Refractive Index substrate temperature 250℃ at 550nm 2.05 ～ 2.1
     Substrate temperature 30℃ at 550nm 1.8 ～ 1.9
Hints on evaporation

     Transmission range 250～2000nm
     Refractive index at 550nm ～ 1.35
Shape---olid substance, Grey-white granules

Specification--- custom-made

Applications---Interference filters, multi-layer coatings.