Firstly, you need to say the words right, there are many names for cenosphere: fillite, fly ash balloon, hollow ceramic microspheres, aluminum silicate cenosphere, micro balloon. Fillite in English, keramische Mikrohohlkugeln in German, Cenoesferas in Spanish
Secondly, you need to know the application of cenosphere.
Cenosphere is widely used in fields like:
construction fields: refractory tiles, interior, anti-slip paints&coatings, anti-noise compounds, cement grout and slurry, fly ash cenosphere brick, pipeline and building adhesive tape, counter top, motors. Low density cement boards.
Oil well fields: cenosphere is used to mixed into low density oilwell cement slurry. Coatings and paintings: cenosphere is use in thermal insulation paints.
Foundry and refractory fields: cenosphere is used in mold casting, GRP, reinforcement fabric, exothermic insulating riser sleeves.
Besides, cenoshpere is used in making surfboard, kayak, bowling ball.
There are many high-tech fields: cenosohere is use in bio- composite, auto body putty, floating system, submarine pipe, EMP shielding formulation