Single crystals of metallic dysprosium have been grown by the Bridgman method and their magnetic properties have been determined in different crystallographic directions of the hexagonal close-packed structure. Below the Neel point of 178.5°K the individual magnetic moments are aligned perpendicular to the Co axis. The moments are aligned in an antiferromagnetic manner from 178.5°K down to 85°K and in a ferromagnetic manner below 85°K. Measurements with the field parallel and perpendicular to the c 0 axis reveal magnetic anisotropy at all temperatures. Below 110°K magnetic anisotropy is also observed in the basal plane. The direction of easy magnetization is along an a ti axis. In the c 0 direction the crystals are extremely "hard" magnetically, the magnetization curves being linear as in the case of a paramagnetic material. The saturation moments follow the T 2 law.The magnetic moments of holmium and thulium metals have been measured in applied fields of 3000-18 000 oersteds, over the temperature range of 4.2-300°K. Holmium, paramagnetic above 133 °K, appears to be antiferromagnetic between 20°K and 133°K, and ferromagnetic below 20°K. Thulium was found to be paramagnetic above 51°K and possibly antiferromagnetic below 51°K.

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