Editing Selenium (section)

===Glass production===
The largest commercial use of selenium, accounting for about 50% of consumption, is for the production of glass. Selenium compounds confer a red color to glass. This color cancels out the green or yellow tints that arise from iron impurities typical for most glass. For this purpose, various selenite and selenate salts are added. For other applications, a red color may be desired, produced by mixtures of CdSe and CdS.<ref name="Ullmann">Bernd E. Langner (2005), "Selenium and Selenium Compounds", ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a23_525}}.</ref>