[en] Nenadkevite samples from uranium bearing albitite and albitation zone of the samples containing the above-mentioned nenadkevite are investigated in detail. The samples are presented rather finely-dispersed products of hydrothermal-metasomatic and hypergeneous processes, therefore the methods of X-ray graphic electron microscopy and microdiffraction were applied for their investigation. Chemical composition and physical properties of the samples are described. The investigation results showed that nenadkevite formations present mainly finest mixtures of X-ray amorphic hydronasturane and urgite type, and more seldom, decrystallized uranium hydrooxides with uranium silicates having crystal structure of boltwoodite-kasolite. A relict uraninite is determined. These mixtures are considered to be formed at changing uranium-nasturane and uraninite oxides