noun🔗Share黑云母 A 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. "花岗岩台面上闪亮的黑色斑点很可能是黑云母颗粒，黑云母是一种云母。geologymineralsubstancematerialchemistryChat with AIVocabulary GamePractice Reading
