Samarium: Oxide Reduced with Graphite at 1700 °C in Vacuum and Distilled Twice (Downing, Gorski and Koerner, US 3,104,970)

Samarium holds on to oxygen too hard for ordinary smelting. Heated with graphite in a hard vacuum it boils off as samarium carbide vapour; a second distillation of that carbide, caught on a tantalum plate, gives the metal itself. Result: samarium metal, 99.7 % pure. Source: J. H. Downing, H. L. Gorski and E. L. Koerner, US 3,104,970 (1963), Example I. Work at 1700 °C under vacuum. Picture drawn by Youblob.