Conversion of isotopic material from metal to compound and vice versa

Often the compound needed out of isotopically enriched material is not readily available. Frequently the isotopically enriched metals are disproportionately expensive compared to the oxide or carbonate. Physical and chemical techniques have to be applied to receive the wanted compound or metal. We describe different procedures to produce 206PbS, 207PbS and 208PbS out of enriched lead, lead nitrate and lead oxide. To obtain the fluorides of 144Sm, 142Nd, 138Ba and 82Sr, chemical techniques are introduced. 48Ca and 144Sm are needed as metal but only the oxide is affordable. The oxides are reduced in a resistively heated tantalum crucible, and the process and the efficiency are discussed.