Kodi pali kusiyana kotani pakati pa alumina ndi white corundum?

Alumina ndi chinthu cholimba kwambiri chokhala ndi malo osungunuka a 2054 madigiri Celsius ndi malo otentha a 2980 digiri Celsius. Nthawi zambiri amagwiritsidwa ntchito popanga zida zotsutsa. Chigawo chachikulu cha corundum ndi α-alumina, yomwe ndi yachiwiri kwa diamondi mu kuuma. Ruby ndi safiro ndi apamwamba kwambiri corundum okhala ndi pang’ono zitsulo oxides osiyana. Ruby nthawi zambiri imakhala yofiira chifukwa imakhala ndi chromium pang’ono, ndipo safiro ndi yabuluu chifukwa imakhala ndi chitsulo chochepa ndi titaniyamu. Kuti

Corundum ndi mtundu wa alumina kristalo wokhala ndi kristalo wabwino, ndipo ubale pakati pa awiriwa ndi wofanana ndi ubale wa kristalo ndi quartz ufa.