Method of fabricating an ltm perovskite product

A method of fabricating a fused product comprising the following steps:

• a′) mixing raw materials providing lanthanum, the element T, and manganese, so as to form a starting charge;
• b′) fusing the starting charge to obtain a molten liquid and casting said liquid;
• c′) cooling said molten liquid until it has solidified completely, so as to obtain a polycrystalline fused product comprising LTM perovskite, L designating lanthanum, T being an element selected from strontium, calcium, magnesium, barium, yttrium, ytterbium, cerium, and mixtures of these elements, and M designating manganese, the product presenting the shape of a block having a thickness greater than 1 mm or the shape of a particle.