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[muhl-ahyt] /ˈmʌl aɪt/
a rare clay mineral, aluminum silicate, Al 6 Si 2 O 1 3 , produced artificially during various melting and firing processes: used as a refractory.
Also called porcelainite.
1924; after Mull, source of the rocks in which it was first identified; see -ite1 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for mullite
  • mullite in refractories increases the fired strength, resistance to deformation under load, and thermal resistivity.
  • Second formed in brightly incandescent area into which a mullite gas-sampling tube is inserted.
  • Exclude plastic refractories and ramming mixes of mullite or extra high alumina.
British Dictionary definitions for mullite


a colourless mineral consisting of aluminium silicate in orthorhombic crystalline form: used as a refractory. Formula: Al6Si2O13
Word Origin
from island of Mull
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Encyclopedia Article for mullite

any of a type of rare mineral consisting of aluminum silicate (3Al2O32SiO2). It is formed upon firing aluminosilicate raw materials and is the most important constituent of ceramic whiteware, porcelains, and high-temperature insulating and refractory materials. Compositions, such as mullite, having an alumina-silica ratio of at least 3:2 will not melt below 1,810 C (3,290 F), whereas those with a lower ratio partially melt at temperatures as low as 1,545 C (2,813 F)

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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