In the course of excavations carried out in 1961-63 and then again in 1982, remnants of a late Roman building and some mosaic fragments -- among others a four-color mosaic of geometrical pattern (250x90) -- were found near Nagyharsány, in southern Hungary. The mosaic was lifted in situ for the purposes of stabilization and presentation as a panel painting. Three layers of gauze were applied to the mosaic by an emulsion called Budaplast. The surface thus stabilized was cut off from the terrazzo embedment by a thin woodfiber panel pushed in between step by step. The terrazzo remains on the back of the mosaic were removed in the laboratory. Smaller gaps were filled with epoxy resin made thixotropic by asbestos wool and aerosel. Afterwards the back of the mosaic was covered with two layers of glass-wool, impregnated by epoxy resin. An aluminum frame of appropriate Tee-sections (210 x 70 centimeters in size) was then attached to this surface together with stiffeners of the same size in the longitudinal and lateral axis. In the cross direction 4 millimeter, hard aluminum wires were fixed in parallel every 8 centimeters. By lapping them over, the frame was stuck onto the back of the mosaic by two thin layers of epoxy resin and glass wool. Thus the surface of the mosaic and the aluminum frame are attached to each other by the 3-4 millimeter thick epoxy resin adhesive. Turning over the mosaic consolidated in this manner, the temporary gauze layer was removed. The surface was cleaned and the missing tesserae of the mosaic were completed by epoxy resin (Eporezit R-3 and FN-20) following the repeating geometrical pattern.