Joint research efforts of a team of scientists at Lobachevsky University of Nizhny Novgorod (UNN) comprising chemists, physicists and engineers are currently focused on solving the problems of handling plutonium and minor actinides (MA) accumulated over many years. To this end, they are studying composite ceramics-ceramics (Cer-Cer) and ceramics-metal (CerMet) materials on the basis of mineral-like compounds (in particular, garnet minerals). Lobachevsky University researchers believe that the optimal solution of the problem is to create high-density ceramic composite inert fuel matrices (IMF) for burning plutonium and transmuting minor actinides.