We are supplying comprehensive raw materials for welding consumables. The specs for wollastonite is showed as below:SiO2 (%): 48.0-55.0 CaO (%): 42.0-50.0 Fe2O3 (% max):1.0 S (% max): 0.03 P (% max):0.03 LOI(% max):2.0 SIZE: -80MESH/-120MESH or according to customer's requirement. Packing: In 1000kg big bag according to customer's requirement.