The present invention relates to a metal alloy, characterized in that it comprises, in percent by weight on the total weight of the alloy, 1-4% of niobium (Nb), 0-0.5% of hafnium (Hf), 27-29% of chromium, 1-5% of nickel (Ni), 0.3-0.45% of carbon (C), 0-2% of tantalum (Ta), 0-2% of titanium, 1-3% of iron, less than 0.5% of manganese (Mn), less than 0.3% of silicon (Si), less than 0.2% of zirconium (Zr), the remainder being cobalt (Co) and unavoidable impurities. This metal alloy has superior mechanical strength characteristics at high temperature which make it suitable for the manufacture of a manufactured article, in particular a spinner, for the production of mineral fibers, such as glass fiber, rock fiber and the like.