... are sodium oxide Na2O,boron oxide(B2O3),silicon dioxide SiO2.Of these ingredients,boron and silicon have high content.The feature of this ... of 1200*650mm,1180*850 with the thickness of 1.5,2,2.25,2.75,3,3.3,4 ... ,5,6,8,10,12,15,20,25,30,50mm.Also ...