The finely divided, red, brown, and yellow soil-colouring minerals originate by what process?
A)mechanical weathering of very fine-grained, blue-grey clays
B)chemical weathering of quartz and feldspars
C)precipitation of insoluble iron oxides during the chemical weathering process
D)mechanical weathering of the feldspars and micas in granite and rhyolite

Question

Quizplus · Accepted Answer

The red, brown, and yellow soil-colouring minerals such as iron oxides originate by the precipitation of insoluble minerals during the chemical weathering process. This precipitation occurs as a result of the oxidation of iron-bearing minerals like pyrite and siderite. Hence, the correct option is C.

The Finely Divided, Red, Brown, and Yellow Soil-Colouring Minerals Originate