Cryolite

Cryolite’s introduction
Cryolite (Sodium fluoroaluminate) is a white crystalline powder or a sandy-size granularity, and a pinkish crystalline powder or a sandy-size granularity as well. Sp.gr.2.95—3.01g/cm3, melting point about 1000°C, specific heat 1.056j/g°C at 18—100°C.Cryolite’s slightly soluble in water, but insoluble in anhydrous hydrogen fluoride. The content of Cryolite’s crystal water will be decreased while the increasing of the molecular ratio, therefore its loss on ignition will be also decreased while the increasing of the molecular ratio. After the paste of synthetic cryolite with different molecular ratio dehydrates, the loss on ignition at 800℃ will appear 10.34%, 6.22% and 2.56% when the molecular ratio reaches 1.74, 2.14 and 2.63 reactively.

Cryolite’s application
Cryolite is mainly used in flux of electrolytic aluminum, pesticide, flux of ceramic colors, anti-rubbing filling agent of resin and rubber, electrolytic liquid for production of iron alloy rimmed steel and furnish of emery wheel.

CHEMICAL COMPOSITION (%)	CH-0	CH-1	CM-0	CM-1
F	≥52	≥52	≥53	≥53
Al	≥12	≥12	≥13	≥13
Na	≤33	≤33	≤32	≤32
SiO2	≤0.25	≤0.36	≤0.25	≤0.36
Fe2O3	≤0.05	≤0.08	≤0.05	≤0.08
SO4 2-	≤0.6	≤1.0	≤0.6	≤1.0
CaO	≤0.15	≤0.20	≤0.20	≤0.6
P2O5	≤0.02	≤0.03	≤0.02	≤0.03
H2O(105~110℃)	≤0.20	≤0.40	≤0.20	≤0.40,
Loss on Drying(500~550℃,1h)	≤2.0	≤2.5	≤2.0	≤2.5

Appearance: Sandy, Powder, Granule
Density:2.95-3.05g/cm3
Size: sandy (80mesh), powder (200mesh, 325mesh), granule (0-10mm).

Cryolite’s physical characteristic
Cryolite has the characteristic of color is clear or white to yellowish, but can also be black or purple; luster is vitreous; transparency crystals are transparent to translucent; crystal system is monoclinic; crystal habits are usually massive and as pseudo-cubic crystals, some with pseudo-octahedral truncations.
Other characteristics: index of refraction is 1.338 which is close to the index of refraction of water. As a consequence, clear cryolite crystals or powdered cryolite will nearly disappear in water. Also there is no salty taste which is helpful in distinguishing cryolite from the mineral.
Packaging of Cryolite
Cryolite can be packed in 25/50/1000kg plastic woven bags with shrink film, or according to customer's requirements.