Cov ntaub ntawv nyoos thiab tshuaj muaj pes tsawg leeg Lub raj mis iav feem ntau muaj 7-12 hom khoom siv raw.Feem ntau muaj quartz xuab zeb, dej qab zib tshauv, limestone, dolomite, feldspar, borax, txhuas thiab barium tebchaw.Tsis tas li ntawd, muaj cov khoom pab xws li clarifiers, colorants, decolora ...
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