A spark plug for an internal combustion engine has one or more electrodes with an electrode material of a platinum (Pt) based alloy. The alloy includes aluminum (Al) and one or more refractory metals selected from the group containing nickel (Ni), rhenium (Re), ruthenium (Ru), tantalum (Ta), molybdenum (Mo), and tungsten (W). In at least some of the disclosed alloys, the aluminum contributes to the formation of an aluminum oxide (Al2O3) layer on a surface of the electrode material.