A method for producing a blank of iron-doped silica glass with high silicic acid content for use as heat protection glass is provided. The method involves: (a) producing an iron-doped SiO2 soot body which contains iron in a first oxidation state Fe3+ by flame hydrolysis of a silicon-containing and an iron-containing starting substance, (b) drying the soot body to obtain a mean hydroxyl group content of less than 10 ppm by weight, and (c) vitrifying the soot body under a reducing atmosphere that is suitable for at least partially reducing the iron from the first oxidation state Fe3+ to a second, lower oxidation state Fe2+. A blank is obtained having an iron content between 0.1 and 1% by weight which exhibits an internal transmission of at most 40% in the infrared wavelength range and an internal transmission of at least 85% in the visible spectral range.