1. A METHOD OF PRODUCING A MAGNESIUM-ENRICHED METAL POWDER FROM MAGNESIUM BASE ALLOY WHICH CONTAINS A SECOND METALLIC COMPONENT WHOSE SOLUBILITY IN THE ALLOY MATRIX VARIES TO A MARKED DEGREE WITH TEMPERATURE AND WHICH, UPON HEAT TREATMENT, LARGELY PRECIPITATES AS AN INTERGRANULAR PHSE, ENRICHED IN THE SECOND COMPONENT AND WHICH ITERGRANULAR PHASE IS RELATIVELY MORE BRITTLE THAN THE GRANULAR PHASE OF THE ALLOY WHICH COMPRISES, HEAT TREATING THE ALLOY IN SOLID PHASE, AT A SELECTED TEMPERATURE SUFFICIENTLY HIGH TO ESTABLISH SUCH EMBRITTLED INTERGRANULAR PHASE, DISINTEGRATING THE HEAT TREATED MATERIAL AND SEPARATING THE GRANULAR FROMT HE INTERGRANULAR MATERIAL.