Under temperate climatic conditions, non-carbonate sandstones are often regarded as non-karstificable. However, regarding solubility conditions of quartzite and ferric oxide binders, the development of karstic forms seems to be possible. To validate or to exclude this assumption, chemical investigation of water and precipitates in a small, gorge-like, non-carbonate sandstone catchment was done. The small stream flowing in the gorge carries silica concentrations around 8 mg/l (as SiO2), pH is slightly alkaline and total iron contents are around 250 ug/l. Lateral tributaries show remarkably lower values of pH, silica concentrations between 9 and 16 mg/l and iron concentrations up to 900 ug/l. The water of stagnant pools has acid pH, often hydrogen sulphide is present, silica concentrations are in a moderate range, and iron concentrations may be high (up to 5.4 mg/l). The concentrations of dissolved silica and total iron indicate that dissolution of both kinds of binders occurs. The development of solutional forms, at domains which are protected from physical weathering within the rock unit, would therefore seem to be possible.

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