Shock temperatures and the melting point of iron

New measurements of the ratio of Fe to LiF and Al2O3 anvil thermal diffusivities are used to obtain revised shock temperatures for Fe. New results match Brown and McQueen's (1) calculations of the temperatures of 5000 and 5800K at the 200 and 243 GPa transitions in Fe. New sound speed measurements along the Hugoniot of gamma-Fe, centered at 1573K, demonstrate that this phase melts at similar to 70 GPa and similar to 2800 K and the gamma phase does not occur above similar to 93 GPa. At higher pressures, perhaps over the entire pressure range of the Earth's molten outer core (132 to 330 GPa), the beta (dhcp) phase, and not the epsilon phase, appears to be the solidus phase of pure Fe.