Cov tshuaj pleev ib ce iav silica yog pheej yig, thiab cov ntsiab lus txhuas hauv nws tsis tuaj yeem tswj tau zoo, yog li peb feem ntau siv nws los faus cov kev phom sij rau lub cev. Peb kuj tseem tuaj yeem zam tsis yuav qhov tsis zoo los ntawm kev them nyiaj ntau dua thaum yuav khoom. Cov iav txhuas. Cov khoom lag luam iav zoo li xim tsaus dua, tsis zoo hauv qhov ntsuas qhov ua kom zoo nkauj, thiab tsis zoo rau tes. Ntau lub sijhawm koj tuaj yeem pom npuas thiab impurities. Lub suab ntawm npuaj nrog koj cov ntiv tes yog npub, thiab cov haujlwm ua haujlwm ntxig me ntsis, thiab cov npoo lossis cov tes ua haujlwm yuav yog koj yuav pom burrs, thiab lub khob zoo li tsaus thiab tsis mus txog qib.
Qee cov iav qib siab ua tiav siv cov iav siv lead ua zoo li cov khoom siv raw, uas muaj cov tshuaj lom hlau hnyav xws li cov hlau lead oxide.Alawm cov tsos zoo nkauj thiab pob tshab, cov txhuas nyob hauv nws yuav raug tso rau hauv dej thaum siv, uas yog tseem heev phom sij.