“…11,12 The basic composition of the pattern glass, hereafter named G11, was derived from glasses A10 and A11 prepared in a previous work. 11,12 Basically, these compositions were within the cordierite primary crystallization field on the 5% CaO plane of the CaO-MgO-Al 2 O 3 -SiO 2 The glass was prepared using commercial chemicals (SiO 2 , Al 2 O 3 , CaCO 3 , MgCO 3 , TiO 2 , and BO 3 H 3 ; Merck, Barcelona, Spain). The calculated batches were mixed and melted in an alumina crucible at 1600°C for 2 h. The melt was poured into water, and the small flakes of glass (frit) formed then were crushed and milled.…”