Bean bauxites of the upper-tobol region / Бобовые бокситы Верхне-Тобольского региона

The carstic bauxite deposits of the western flange of the Turgai trough are investigated in geological, petrological, mineralogical, and morphological aspects, as well as to the chemical composition. Special attention was paid to the so-called »beans«, inclusions in the cement of the stony bauxites of that region. These beans have an average diameter from 2 to 20 mm, greater ones are rare, and so are varieties smaller than 1 mm. Structurally, they consist of a gray ferrum-alumi-nium core around which a black coating of alumina-ferruginous matter is wrapped.
The inner composition of the beans was examined very carefully in every respect, and on that base some new suggestions about their genesis was put forward.