... 10% Moisture: (%) < 1%... Cenospheres are hollow ceramic microspheres found in flyash, a natural by-product of coal combustion during the ... hollow, microspheres are used as functional fillers or extender in the manufacture of plastics, paints,resins, thermal coatings, ... their many uses, microspheresare used as light weight aggregate in oil well cements, sound proofing,thermal insulation, interior and ...