noun🔗ShareBiotiteA dark brown mica; it is a mixed aluminosilicate and fluoride of potassium, magnesium and iron."The shiny black flecks in the granite countertop are likely grains of biotite, a type of mica. "Les paillettes noires brillantes dans le comptoir en granit sont probablement des grains de biotite, un type de mica.geologymineralsubstancematerialchemistryChat with AIVocabulary GamePractice Reading
