Barium sulfate is an economical and commonly used reflective coating. It offers a diffuse reflectance characteristic within the wavelength range from 300 nm to 2400 nm. Typical reflectance is ~ 97 % at 600 nm but can be adjusted to ~ 80 % to reduce substitution effect errors caused by high reflectance. In certain photometric applications. A more durable coating than the standard paint ODP97 but with slightly less reflectance can be supplied as required.