• 4 November, 2023
  • 9:43 am
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An off-white, grayish, brown, yellow, or reddish-brown rock composedof a mixture of various amorphous or crystalline hydrous aluminum oxides and aluminum hydroxides (principally gibbsite, some boehmite), and containing impurities in the form of free silica, silt, iron hydroxides, and especially clay minerals; a highly aluminous laterite