The "fine blue color" Davy observed is now associated with solvated electrons that are formed (along with solvated metal cations) when alkali metals are dissolved in ammonia at low concentrations. Curiously, the color of the solutions does not depend on the identity of the metal atom, but it does depend on the metal's concentration, with the solution gradually becoming gold and metallic near 8 mole percent metal (MPM), and remaining gold at saturation (∼20 MPM for lithium). A comprehensive review of the discovery, properties, bonding and discussion of the molecular entities that might comprise metal ammonia solutions is presented in Ref. Though numerous chemical species, at various concentrations, have been proposed to constitute metal ammonia solutions, the general equation for electron solvation, using lithium metal as an example, is: