Future X-ray space missions will require telescopes with very large effective area, good angular resolution and low weight. To obtain these characteristics it is necessary to produce very thin and light mirror shells that, once integrated into a suitable mechanical structure, will fulfil the requested specifications. To meet these requirements, one approach which seems promising is the use of ceramic materials combined with the plasma forming technology to produce ceramic carriers that are subsequently used to manufacture the x-ray mirror shells by means of the epoxy replication technology on superpolished mandrels. The CEA/Le Ripault has shown the feasibility of producing ceramic carriers (diameter: 600 mm, height: 239 mm). The mass saving is substantial in comparison with the nickel electroforming technology which is now used to manufacture high throughput, medium angular resolution x-ray optics. The achieved out of roundness of the carriers is ± 70 microns; an effort must still be made to meet the requested specification of ± 20 microns.