A abun da ke ciki na tubalin yumbu

Tubalin yumbu sun ƙunshi mullite (25% -50%), lokacin gilashin (25% -60%), cristobalite da quartz (har zuwa 30%). Yawancin lokaci ana amfani da yumbu mai wuya a matsayin albarkatun kasa, kayan da suka balaga za a fara ƙididdige su, sa’an nan kuma a haɗe yumbu mai laushi tare da hanyar bushewa ko hanyar filastik don samar da kayan bulo na yumbu. Abubuwan da aka ƙone da kayan amorphous. Ana amfani da shi sosai a cikin tanderun fashewa, tanda mai zafi, tanda mai dumama, tukunyar wuta, kiln lemun tsami, kilns na rotary, yumbu mai jujjuya bulo mai harbin kilns.