Calcined singano coke ndi yosiyana kwambiri ndi siponji coke mu katundu, ndi kachulukidwe mkulu, chiyero mkulu, mphamvu mkulu, otsika sulfure okhutira, otsika ablative mphamvu, otsika matenthedwe kukulitsa coefficient ndi zabwino matenthedwe kukana kugwedezeka.