Characteristics: Silver-white solid or gray to black powder. Tensile strength 80,000 psi; high modules of elasticity. Attacked by strong oxidizing agents (nitric and sulfuric acids). Practically insoluble in hydrochloric acid. Retains its crystal structure all the way to its melting point. Has the widest range of valences of any element. Rhenium-molybdenum alloys are superconductive at 10 K. Not attacked by sea water.
Hazards: Flammable in powder form.