Abstract :
[en] Spring, W. N. Jahrb. f. Mineral (1899), 47-62; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010).
Author arrives to the conclusion that not the emergence of the red color, but those the yellow consequence is a more complicated chemical process. Chemically pure ferric oxide becomes hydrated under waters automatically ferric oxide. This spontaneous drainage will have colored all sediments wine red, if ferric oxide hydrate had remained for itself, now is received it however with strange oxides compounds, and is these chromogenic, then the product is yellow to brown, if really heterogeneous groups are present, in other set-up, depending upon the number of Fe2O3-Groups, more or less red. The red sediments will from this an agreed transfer of this two sediments to present: a mechanical (sand or Thon) and a coloring as consequence of chemical processes. The humus materials reduced the dissolved iron compounds (see Bull. Acad. roy. Belgique 34. 578-600; C. 98. I. 410) and a precipitation of humus-acid ferrous oxide on the Sandoder thin particles produces. The approximated and magnesium compounds were held back by the CO2 water. The manganese divides the fate of the iron. The Fe-Mn-precipitation is assailed by that dissolved O and the SiO2. The O works it because of the ferric oxide burning, forms for water and CO2. As transition materials and spathic manganese seem inevitable. The SiO2 reacted to the fresh carbonates, it develops silicates, which work cementing and which against further oxidation protect ferrous oxide. Depending upon the quantity of the humus-acid iron salts ferric oxide remains and colors violet red as firm oxide after terminated burning, or the SiO2 is able to hold every iron, whereby green layers develop. The more SiO2 is present, the more disappears the red color. The yellow rocks are assailed by HCl, without a greener residue remains, therefore must the sedimenting without reduction features have taken place at one time here. The iron compounds were connected to them with SiO2 and other oxides are associated, so that the humus materials could not react, those were suspended than yellow sludge in the water. One can say thus, the red deposit originates from clear, the yellow from cloudy water. The yellow sediments are stable, on the other hand it is not impossible that red gradually by penetration of acid water etc. become yellow.
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