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matte1
adj.1. having a dull or lusterless surface: matte paint; a matte complexion; a photograph with a matte finish.n.2. a dull or dead surface, often slightly roughened, as on metals, paint, paper, or glass.3. a tool for producing such a surface.4. Metall. an unfinished metallic product of the smelting of certain sulfide ores, esp. those of copper.5. Motion Pictures. See matte shot.v.t.6. to finish with a matte surface.[1640-50; < F mat (masc.), matte (fem.), OF < LL mattus moist, soft, weak, perh. < *maditus, deriv. of L madere to be wet]matte2/mat/, n. Mining.a mass of timber caved beneath overburden so as to cushion the fall of the overburden and separate it from mineral to be extracted beneath.[ < G; akin to MAT1]
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crude mixture of molten sulfides formed as an intermediate product of the smelting of sulfide ores of metals, especially copper, nickel, and lead. Instead of being smelted directly to metal, copper ores are usually smelted to matte, preferably containing 40–45 percent copper along with iron and sulfur, which is then treated by converting in a Bessemer-type converter. Air is blown into the molten matte, oxidizing the sulfur to sulfur dioxide and the iron to oxide that combines with a silica flux to form slag, leaving the copper in the metallic state. Smelting of nickel sulfide ores yields a matte in which nickel and copper make up about 15 percent, iron about 50 percent, and sulfur the rest; the iron is removed in a converting furnace, and the sulfides of copper and nickel are separated before being reduced to the metals. Smelting of lead sulfide ores produces a liquid layer of copper sulfide matte that can be decanted, along with slag and speiss, from the lead bullion.* * *
Universalium. 2010.
