A reactive sintered magnetic article, a composite article comprising a mantle and at least one core and a laminate article comprising two or more composite articles are provided which each comprise (La.sub.1-aM.sub.a) (Fe.sub.1-b-cT.sub.bY.sub.c).sub.13-dX.sub.e, wherein 0.ltoreq.a.ltoreq.0.9, 0.ltoreq.b.ltoreq.0.2, 0.05.ltoreq.c.ltoreq.0.2, -1.ltoreq.d.ltoreq.+1, 0.ltoreq.e.ltoreq.3.