| Molecular formula:K2SiF6 Molecular weight :220.26 Properties: white crystal or powder , hexagonal   crystal Relative density 3.08.  Uses: wood preservative, glass, insecticide, ceramic   and synthetic mica Quality standard: 
                     
                       | Index name | Index  |  
                       | Second grade  | First grade  |  
                       | Assay % | ≥98.0 | ≥99.0 |  
                       | Free acid(H2SiF6)% | ≤0.5 | ≤0.1 |  
                       | Sulfate (SO4)% | ≤0.02 | ≤0.02 |  
                       | Chloride (Cl) % | ≤0.1 | ≤0.1 |  
                       | Heavy metals(Pb)% | ≤0.01 | ≤0.01 |  
                       | Moisture % | ≤0.5 | ≤0.2 |  
                       | Fineness on 80 mesh screen % | 90 | 100 |  
                       | Water insoluble matter % | ≤0.5 | ≤0.1 |  Packing:net wt. 25kg, plastic woven bag.
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