QS	Quartz sand
GS	Glass sand
U	Heat transfer coefficient (W/(m2·K))
CT	Computed tomography
SEM	Scanning electron microscope
ASt1 TRAD	Traditional (reference) silicate brick (lime-sand, 90% quartz sand)
ASt2 50%GS	Silicate brick with 50% glass sand and 50% quartz sand in relation to the sand volume in the raw material mass (90% SiO2)
AST3L	90% glass sand (complete elimination of quartz sand)