Bulk amounts of La@C-82 and Gd@C-82 have been isolated in pure form from various hollow fullerenes. Magnetization data for these powder samples, an isolated La@C-82 isomer and a Gd@C-82 isomer, have been obtained employing a SQUID magnetometer at temperatures ranging from 3 to 300 K. For La@C-82 the inverse susceptibility as a function of temperature follows a Curie-Weiss law. The effective magnetic moment per La@C-82 is 0.38 mu(B). For Gd@C-82 the magnetization data fall on a universal curve which is fitted to a Brillouin function in correspondence with the Gd3+ free ion ground state values of J = 3.38 and g = 2.