noun🔗ShareالكونرندAn extremely hard mineral, a form of aluminum oxide with the chemical formula Al2O3, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive."Because of its hardness, corundum is used in sandpaper to smooth rough wood. "بسبب صلابته، يستخدم الكونرند في ورق الصنفرة لتنعيم الخشب الخشن.mineralmaterialgeologysubstancechemistryscienceChat with AIVocabulary GamePractice Reading