Bismuth oxide 99.9% min. for for varistor and thermistor,for glass cover of kinescope usage, ITEM STANDARD TEST RESULT Bi2O3 99.9% min. 99.93% Sb 30ppm max. 6ppm Fe 30ppm max. 5ppm Pb 10ppm max. 3ppm Cu 10ppm max 3ppm As 30ppm max. 1ppm Si 10ppm max. 5ppm D50 0.2um~0.5um. 0.26um Packing: in 25kgs fiber drums.