Quartz iav
Quartz iav yog tsim los ntawm melting txhua yam ntawm ntuj ntshiab quartz (xws li siv lead ua, quartz xuab zeb, thiab lwm yam). Cov kab sib hloov qhov tso tawm yog qhov tsawg heev, 1/10 ~ 1/20 ntawm cov iav zoo tib yam, thiab nws muaj zoo thermal poob siab.