The present invention relates to a glass ceramic material comprising a core-rim structure, wherein the core-rim structure comprises an amorphous SiO.sub.2 matrix, ZrO.sub.2 crystals, and hardness-enhancing additive, the ZrO.sub.2 crystals are present in cores that are at least partly surrounded by a rim comprising hardness-enhancing additive.

Ceramic colours containing effect pigments and a liquid glass forming component for decoration of metallic, ceramic and glassy articles and a process for the preparation of a ceramic glaze.

A method of manufacturing polycrystalline abrasive elements consisting of micron, sub-micron or nano-sized ultrahard abrasives dispersed in micron, sub-micron or nano-sized matrix materials. A plurality of ultrahard abrasive particles having vitreophilic surfaces are coated with a matrix precursor material in a refined colloidal process and then treated to render them suitable for sintering. The matrix precursor material can be converted to an oxide, nitride, carbide, oxynitride, oxycarbide, or carbonitride, or an elemental form thereof. The coated ultrahard abrasive particles are consolidated and sintered at a pressure and temperature at which they are crystallographically or thermodynamically stable.

A method of diffusing one or more of gold nanoparticles, silver nanoparticles, gold ions, and silver ions, into a solid transparent material, causing it to absorb at least some wavelengths of visible light, UV light, or both, the method comprising: (a) providing a first volume of organic solvent with one or more of gold nanoparticles, silver nanoparticles, gold ions and silver ions, blocked with one or more ligands, suspended in the organic solvent; (b) adding a quantity of the volume of organic solvent to a volume of water; (c) immersing the transparent material in the volume of water; and (d) heating the volume of water with the added organic solvent and the transparent material for a period of time, causing the one or more of gold nanoparticles, silver nanoparticles, gold ions and silver ions to diffuse into the transparent material.

A glass structure includes: a plurality of glass particles, each of the glass particles including SiO.sub.2, CaO and P.sub.2O.sub.5; and a bonding portion that bonds the glass particles to one another and contains hydroxyapatite, wherein at least a part of the hydroxyapatite is crystalline in the bonding portion, and wherein a porosity of the glass structure is 15% or less. A method for producing the glass structure includes: preparing a mixture by mixing a plurality of glass particles and an aqueous solution with each other, each of the glass particles including SiO.sub.2, CaO and P.sub.2O.sub.5, and the aqueous solution including calcium and phosphorus and having pH of 4.0 or more; and heating and pressurizing the mixture.

Ceramic colours containing effect pigments and a liquid glass forming component for decoration of metallic, ceramic and glassy articles and a process for the preparation of a ceramic glaze.

A conductive paste includes electrically conductive particles, a binder, an organic solvent, a glass powder, and a specific amount of inorganic oxide particles that are at least partially surface-coated with an organophosphorus compound and have a specific average particle size. Solar cell electrodes formed by firing the conductive paste have increased bond strength with a substrate.