The enrichment of germanium-73 with the magnetic isotope effect (MIE) succeeded, for the first time, in the presence and absence of magnetic fields. At 200 G, the photolysis of methyltriphenylgermane in a Brij35 micellar solution under 92.8% conversion gave the 4% enrichment of germanium-73 (alpha = 0.015). Germanium-73 is the heaviest magnetic isotope to have so far been enriched with MIE from samples of natural abundance.