... rubber, plastics, etc. Cenosphere is widely used as filler material in various industries such as Oil drilling industry, cement, rubber, plastics, resins, ... .5-4.0% MgO 0.8-1.5% Our specification as follow:Name of commodity: CenospheresColor: Grey whiteChemical component: SiO2: ... Packing: 25KG per bag We can do different particle size as your required, If you have interesting, please contact us. ...