Abstract: A panel of anistropic material comprising acicular crystals enclosed in a vitreous or ceramic matrix. The crystals are oriented perpendicular to the opposite faces of the panel and traverse the panel from one side to the other.

Abstract: A method for manufacturing a panel of anisotropic ceramic glass comprising acicular crystals enclosed in a vitreous matrix, the crystals being orientated perpendicularly to the panel faces and traversing the panel from one side to the other, in which a homogeneous mineral composition capable of forming a ceramic glass is subjected to heat treatment consisting of bringing said layer to a temperature at least equal to its working temperature and greater than the crystallization temperature of the crystalline phase, and establishing therein a thermal gradient perpendicular to its faces, and then progressively and gradually lowering the temperature of the layer starting from one of its faces, in such a manner as to successively bring each transverse plane of the layer to a temperature lower than the crystallization range of the crystalline phase, so as to induce nucleation of the crystalline phase in that face plane which is at the lowest temperature while maintaining the thermal gradient such as to orientate the

Abstract: A method of protecting an object from fire damage by coating the object with a slurry made from hydrated metal silicate particles and an aqueous alkali metal silicate solution. The slurry is applied before there is significant absorption of water into the particles from the solution. Upon heating, the coating expands to form a foam which, because of the equilibrium of water formed between the particles of sodium silicate, is rigid at high temperatures.

Abstract: A biocompatible glass ceramic consisting of a vitreous matrix containing vitreous inclusions in which are dispersed crystals of a compound, isomorphous with hydroxyapatite, of at least the following elements: calcium, a lanthanide or yttrium, silicon, phosphorus and oxygen, these inclusions being surrounded by crystals of at least one compound belonging to the group consisting of Na.sub.2 Ca.sub.2 Si.sub.3 O.sub.9 and Ca.sub.3 (PO.sub.4).sub.2.2 Ca.sub.2 SiO.sub.4, can be used to construct artificial bone segments etc in bone surgery and bonds firmly with the new bone tissue without causing inflammation.