Definition of macle in US English:



  • 1A diamond or other crystal that is twinned.

    • ‘Good brown macle twins up to several carats in weight have been available in recent years from the Udachnaya mine.’
    • ‘Flattened contact twins are known in the gem trade as macles.’
    • ‘Almost all the creeks that have produced gold crystals have produced triangular spinel-twinned crystals or macles.’
  • 2

    another term for chiastolite
    • ‘The variety chiastolite (also called cross-stone, or macle) forms long prisms in a cross section.’
    • ‘The chiastolite, or macle, shows the representation of a cross on its surface, this effect being produced by the regular arrangement of carbonaceous impurities along the axes of the crystal.’


Early 19th century: from French, from Anglo-Latin mascula ‘mesh’.