Ubutare bwa kobalitite (CoAsS) — ni ubutare bw'ibara rya feza yera kugeza ku bwijimye bukungahaye kuri kobalti, arsenike na sulufure. Ni bwo soko nyamukuru ya kobalti, kandi kuva mu bihe bya kera bukoreshwa mu gutanga ubururu bwimbitse ku birahure n'ibikoresho by'ibumba (sumalita, ubururu bwa kobalti). Ibigize arsenike n'ibigize kobalti byose bifite uburozi — bikoreshwe wambaye ikirinda ubuhumekero.