Definition of hornblende in English:



mass noun
  • A dark brown, black, or green mineral consisting of a silicate of calcium, magnesium, and iron, occurring in many igneous and metamorphic rocks.

    • ‘One of the rarer minerals is hornblende, which is also found with crystals of quartz.’
    • ‘The granite is porphyritic with biotite and hornblende as important minerals and lies to the south of the contact; the gneiss lies to the north of the contact.’
    • ‘The main constituent phases of these rocks are plagioclase, hornblende, pyroxene, quartz and K-feldspar, and accessory phases include magnetite, sphene, zircon and apatite.’
    • ‘Although each mound had substantial amounts of quartz and kaolinite, minerals that reflected differences in mound material included magnetite, gypsum, hornblende, hematite, goethite, and feldspars.’
    • ‘All four samples are medium-grained, and comprise variable proportions of hornblende, feldspar and quartz with accessory biotite and titanite.’


Late 18th century: from German, from Horn ‘horn’ + blende (see blende).