Low-iron glass is a type of high-clarity glass that is made from silica with very low amounts of iron. This low level of iron removes the greenish-blue tint that can be seen especially on larger
and thicker sizes of glass.Low-iron glass is used for aquariums, display cases, some windows, and other applications where clarity is desired.
Low-iron glass typically has a ferric oxide content of about 0.01%. Ordinary plate glass has about 10x as much iron content. Low-iron glass is made from low-iron silica sand. In the United States,
the primary sources for such sand are in Wisconsin.
Fallingwater, a house designed by Frank Lloyd Wright and built in 1939, was one of the first houses to use low-iron glass for windows.
Low iron glass is widely used in solar panels
Low-iron glass is sold under various brand names. Guardian Industries calls it "Ultrawhite". Pilkington calls it "Optiwhite".PPG Industries calls it "Starphire". Other brand names include
"Starlite", "Krystal Klear", "Diamant" and "Eurowhite".