Density filler material

Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume.

Note: Greek letter $\zeta$ is used because both the Greek letter $\rho$ and the Latin letter $D$ were in use.

Symbol
$\zeta_{f}$
Unit
g/cm$^3$
Related
$\zeta_{M}$
Used in
$m_{f}$