[en] A tetravalent uranium phosphate-ningyoite for the first time has been discovered in stratum epigenetic uranium deposit in the USSR. Application of electron microscopy combined with microdiffraction and micro X-ray spectral analysis promoted the discovery. The investigation has been carried out with an aid of electron microscopy supplied with the ''Kevex Ray'' goniometer and microprobe attachment. Spendle-shaped crystals of ningyoite, their fractures and more seldom-stellar concretions are discovered in finely dispersed mineral mixture of sample, selected from grey-green sandstone with spots of red iron hydrooxides. Electron cell of the crystals corresponds to the one of ningyoite, described by Muto. The discovered law of declinations, characterizes one of the spatial groups with base - centered lattice of the rhombic crystallographic system Cmmm; C222; Cmm 2, Cm2m. P, U, Ca elements have been determined in tha ratio P:U:Ca=2; 0,6-0,9; 1,4-1,4. The clarified ningyoite formula appears in the form of Casub(2-x)Usub(x)(PO₄)₂xH₂O where x <=1