Bikozwe mu byuma bya karubone.Bikozwe muri # 45 ibyuma cyangwa # 60 ibyuma.Bitunganywa no gushushanya insinga, annealing, gukora imisumari, kuzimya nibindi bikorwa, birakomeye.Igikorwa cyayo ni ugutera imisumari kubintu bimwe bikomeye imisumari idashobora, kubera ko ibikoresho bitandukanye cyane nimisumari isanzwe, whick ni iy'imisumari idasanzwe.Ubukomere bw'imisumari ni larde cyane kandi ni ngufi, kandi ubushobozi bwo kwinjira burakomeye.