Red Iron
Iron is commonly used as a colorant in its red iron oxide form as (Fe2O3). Red iron oxide is commonly used to produce earthy reds and browns. It is the metal responsible for making earthenwares red. Iron is also another tricky colorant because of its ability to yield different colors under different circumstances. At low percentages (.5-1%) and in the presence of potassium, iron will become light blue or light blue-green in reduction (as is seen in traditional celadons). In the presence of barium, iron may become yellow green. When used in combination with calcium, red iron oxide can become pale yellow or amber in oxidation or green in reduction. Common percentages for red iron oxide range from (4 up to 10%).
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Famous quotes containing the words red and/or iron:
“The Red Cross in its nature, it aims and purposes, and consequently, its methods, is unlike any other organization in the country. It is an organization of physical action, of instantaneous action, at the spur of the moment; it cannot await the ordinary deliberation of organized bodies if it would be of use to suffering humanity, ... [ellipsis in original] it has by its nature a field of its own.”
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“Or bid the soul of Orpheus sing
Such notes as, warbled to the string,
Drew iron tears down Pluto’s cheek,
And made Hell grant what love did seek;”
—John Milton (1608–1674)