Abstract: A magnetocaloric refrigerator uses as a refrigerant a magnetocaloric refrigerant material of the perovskite structure containing lanthanum and also containing Ce, Pr and Nd which may be of the general formula: LalCecPrpNdnRErAaMnXxO3?? wherein: A is at least one of the alkaline earth metals X if present is at least one metal selected from the group consisting of Co, Mn, Fe, Ni, Zn, Cu, Al, V, Ir, Mo, W, Pd, Pt, Mg, Ru, Rh, Cr and Zr, RE if present is at least one lanthanide other than La, Ce, Pr and Nd, the ratio of (l+c+p+n+r+a):(l+x) is from about 1:0.95 to about 1:1.15, the ratio of (l+c+p+n+r):(a) is from about 5:4 to about 7:2, x is from 0 to about 1:0.15, and ?1<?<1.