Abstract: A Y.sub.3 Al.sub.5 O.sub.12 :Tb and method for producing the phosphor are disclosed. The method invloves forming a uniform mixture of source materials for Y.sub.3 Al.sub.5 O.sub.12 :Tb phosphor and barium fluoride with the barium fluoride being present in the mixture at a level of from about 0.254 to about 7.61 weight percent, and firing the mixture at an elevated temperature to react the source material to form the phosphor. The phosphor has an improved brightness of at least about 75% over a phosphor of the same type produced without the barium fluorides.

Abstract: A method is disclosed for producing pure cobalt metal powder. The method involves reducing a cobalt containing source material to produce an intermediate cobalt metal, contacting this intermediate with an ammoniacal ammonium halide solution and a catalyst with oxidation to form a solution of hexamminecobalt(III) ions, removing insoluble material, and adding a sufficient amount of a halide salt to the solution to precipitate hexamminecobalt(III) halide which is separated from the mother liquor. The hexamminecobalt(III) halide precipitate is dissolved in water and the pH is adjusted to greater than about 10 with a base, while the solution is heated at a sufficient temperature for a sufficient time to form an insoluble cobalt oxide containing material which is separated from its mother liquor and reduced to pure cobalt metal powder.