... crystal, white powder, granular crystal or prill. Potassium carbonate tech grade is monoclinic crystal, white powder, granular crystal or prill ... )% Max0.01Sulphate (as K2SO4)% Max0.01Iron% Max0.001Insoluble matter in water% Max0.02Burnt loss% Max0.6Arsenic% Max0.0003Heavy Metal(as Pb ... electroplating, tanning, ceramic, building materials, crystals and medicine. Potassium carbonate tech grade