Dross is a mass of solid impurities floating on a molten metal or dispersed in the metal, such as in wrought iron. It forms on the surface of low-melting-point metals such as tin, lead, zinc or aluminium or alloys by oxidation of the metal(s).
With wrought iron, hammering and later rolling, removed some dross. With tin and lead the dross can be removed by adding sodium hydroxide pellets, which dissolve the oxides and form a slag. Dross can also be skimmed off.
Dross, as a solid, is distinguished from slag, which is a liquid. Dross product is not entirely waste material; aluminium dross, for example, can be recycled and is used in secondary steelmaking for slag deoxidation.
Read more about Dross: Etymology and Usage
Famous quotes containing the word dross:
“At fifteen one is first beginning to realize that everything isn’t money and power in this world, and is casting about for joys that do not turn to dross in one’s hands.”
—Robert Benchley (1889–1945)
“Was this the face that launched a thousand ships,
And burnt the topless towers of Ilium?
Sweet Helen, make me immortal with a kiss.—
Her lips suck forth my soul; see where it flies!—
Come, Helen, come, give me my soul again.
Here will I dwell, for heaven be in these lips,
And all is dross that is not Helena.”
—Christopher Marlowe (1564–1593)