The magnetic moment and hysteresis properties of a high‐density nearly completely oriented Co5Sm magnet alloy have been measured from 300 to 4.2 K and in applied fields up to 140 kOe. A saturation moment per gram of 98 G cm3/g is measured at 300 K and shows a slight increase as temperature is decreased. After adjustment for voids and oxide, the saturation moment per gram of the Co&sngbnd;Sm alloy is 102 G cm3/g, or equivalent to 11 000 G for the saturation magnetization 4&pgr;Js. An energy product of approximately 24 MG Oe is attained at 300 K.