In this report, we describe the use of the Mg2+/0couple as a reference in molten MgCl2-NaCl. We demonstrate that this redox couple provides a robust and reliable reference potential over a range of melt temperatures (500 °C-675 °C). Finally, we demonstrate the construction of a simple molten magnesium reference electrode, for operation at temperatures greater than the melting point of magnesium (650 °C).