This reference (1) is not specific to SiO.sub.2, (2) does not teach or suggest that a brick with a high content of SiC (or of SiO.sub.2) will produce less physicaladherence, (3) does not address the influence of the presence of zinc (if any) on such adherence, and (4) does not teach any brick surface treatment per se, fused or otherwise.The present invention, however is particularly addressed to m