Refractometer is an optical instrument used to measure the index of refraction of a substance or some physical property of a substance that is directly related to its refractive index. Certain types of refractometers can be used for measuring gases, liquids, and even transparent or translucent solids such as gemstones. It can also be used to determine the identity of an unknown substance based on its refractive index, to assess the purity of a particular substance, or to determine the concentration of one substance dissolved in another.

Refractory coating is a layer of refractory material used to insulate or to isolate a kiln wall from the effects of gases of kiln shelving from the fluxing of bodies and glazes. It is usually administered as thin slurry painted on the surface and called flint wash, zircon wash, aluminum oxide wash. The choice of refractory depends upon the type of protection required.

Refractory coating is a thermal barrier coating. It is made of refractory material.

Refractory metals are metals that have resistant to heat, wear, and corrosion. These are used in lighting, tools, lubricants, nuclear reaction control rods, as catalysts, and for their chemical or electrical properties. These are characterized by their extremely high melting points, which range well above those of iron and nickel. The five refractory metals are tungsten, molybdenum, niobium, tantalum and rhenium. Physical properties of refractory metals, such as molybdenum, tantalum and tungsten, their strength, and high-temperature stability make them suitable material for hot metalworking applications and for vacuum furnace technology.