The translucent or opaque
colored glass-
ceramic article provides a cooking surface and has an adjustable
light transmission in a
visible range under 15%, as measured for a 4 mm sample thickness; a flaw-free upper surface with an
impact resistance of greater than 18 cm breaking height, as tested with a 200 g
steel ball in a falling ball test; a
temperature difference resistance of greater than 500° C.; a high
crystallinity with
keatite mixed crystals as principal
crystal phase in an interior of the glass-
ceramic article and with a residual glass
phase fraction of less than 8% by weight; a glassy upper
surface layer of from 0.5 to 2.5 μm thick, which is substantially free of high
quartz mixed crystals and which inhibits chemical reactions, and a content of enriched ingredients in the residual glass phase in the interior of the glass-
ceramic and in the glassy
surface layer of ΣNa2O+K2O+CaO+SrO+BaO+F+refining agents of from 0.2 to 1.6% by weight.