embodiment oxidation of the objects consisting essentially of thoriated tungsten pieces to form thorium containing or thorium oxide containing tungsten oxide pieces chemical reduction of the homogenized tungsten oxide pieces under a hydrogen gas atmosphere to form thoriated tungsten pieces the starting material for the oxidation step is waste consisting essentially of tungsten contaminated with thorium oxide and other impurities starting materials include defective lamp parts of thoriated tungsten and scrap pieces or residues which are produced during the manufacture of thoriated tungsten lamp electrodes such as for example chips filings wires bars or rods and foils or sheets the starting material is sorted according to form and if necessary subjected to different commutation processes depending on the form foils and wires will be comminuted in a shredder while rods or bars will be comminuted into granules in a suitable crusher preferably the pieces will be small e g order of magnitude of a few microns and preferably about 1 5 2 u03bcm to ensure a homogenous recycled product no commutation process is required for filings the duration of the oxidation step depends on the size of the pieces used or obtained by the commutation process the thoriated tungsten pieces which have been comminuted if required are oxidized in air in a furnace by means of a heat treatment carried out in a temperature range between approximately 400 u00b0 c and 1200 u00b0 c the most preferred temperature range for the oxidation step is 550 u00b0 to 650 u00b0 c the oxidation step can be carried out at 600 u00b0 c for example the.