An electrochemical series of redox couples has been developed for use in silicate melt systems that model basaltic magmas. The redox couples are ordered in terms of their reference reduction potentials, which are measures of their ease of reduction in silicate melts. Although the numerical value of the reference reduction potential for a particular redox couple is quite sensitive to the exact melt composition and temperature, the order of the couples in the series appears to be relatively independent of these variables. Thus, upon calibration to a desired composition, oxygen fugacity, and temperature, this electrochemical series can provide estimates of redox state proportions in basaltic magmas on different planetary bodies. The geochemical electrochemical series can also be used to understand the interrelationship of the redox state of the magma and the presence of volatile species such as oxygen, water, sulfur gases, and carbon gases. ¿ American Geophysical Union 1987