The density is its mass per unit volume. For its calculation both parameters have to be determined. While the mass can be ascertained easily by weighing, the determination of the volume of irregular formed solids is more difficult.
As solution three different methods come into consideration:
Buoyancy method: The test piece supersedes the commensurate liquid volume; the superseded mass is ascertained by differential weighing in water and in the air.
Floating equilibrium method: The test piece plunges in a liquid with approximately equal density; by temperature change the liquid’s density is adapted until the test piece floats.
Pycnometer method: The determination of the volume is performed by plunging the test piece in a liquid.
(Samples: massive glass samples, circa 8 x 8 x 8 mm or smaller, 2-3 parts, for buoyancy method greater parts possible)