... , paint, ink, pottery, glass, toothpaste, rubber, pigment, dately used product industry, also as food additive and anti-acid agent in pharmaceutical ... industry, as high-quality filler and reinforcement agent of rubber products, ... -0.004loss on ignition ≤54-5854-58≥ 52.054-58Accumulation density ≤g/ml0.120.14-≥0.4Screen Residues≤150um0.0250.030 ...