  The p-V-T equation of state of magnesium metal has been measured up to 20 GPa
and 1500 K using both multianvil and opposite anvil techniques combined with
synchrotron X-ray diffraction. To fit the experimental data, the model of
Anderson-Gr\"uneisen has been used with fixed parameter {\delta}T. The 300-K
bulk modulus of B0 = 32.5(1) GPa and its first pressure derivative, B0' =
3.73(2), have been obtained by fitting available data up to 20 GPa to Murnaghan
equation of state. Thermal expansion at ambient pressure has been described
using second order polynomial with coefficients a = 25(2)x10-6 K-1 and b =
9.4(4)x10-9 K-2. The parameter describing simultaneous pressure and temperature
impact on thermal expansion coefficient (and, therefore, volume) is {\delta}T =
1.5(5). The good agreement between fitted and experimental isobars has been
achieved to relative volumes of 0.75. The Mg melting observed by X-ray
diffraction and in situ electrical resistivity measurements confirms previous
results and additionally confirms the p-T estimations in the vicinity of
melting.
