[en] A study has been made of the structure and the phase composition of microspheres obtained from ZrO₂ with an addition of 8.7 mol.% Y₂O₃ produced by the spheroidization of the charge powder in low-temperature air high-frequency plasma. It has been established that the microspheres have a specific morphology of the forming crystals. One portion of the microspheres is transparent and by its structure comes close to monocrystals, while the other portion has a mat surface and represents polycrystals. The ratio between the number of monocrystal and polycrystal microspheres depends on their diameter. The production of monocrystal microspheres is being facilitated with the reduction of the diameter. For a diameter in the range of 40-60 μ their share amounts to 20-3O %