This instrument is used for determination and checking of bitumen percentage in bitumenous mix, the mix is added with a solvent and disolved bitumen is removed by centrifugal action. It consists of a removable aluminium rotor bowl, capacity 1500 gms, with a cap and tightening nut. The bowl assembly is mounted on a vertical shaft which produces from a cast housing. This shaft and the bowl is rotated fast manually by enclosed gears in the cast body and handle. Solvent is introduced during the test through the holes in the cap of the housing. A drain is provided to collect disolved bitumen coming out of the rotating bowl and getting collected in the housing.