∙ A pale brown mineral of the mica group, being a basic potassium aluminosilicate with the chemical formula KAl2(Si3Al)O10(OH,F)2; used as an electrical insulator etc. mineralogy
Muscovite
Noun
∙ An inhabitant or native of Muscovy or Moscow.
∙ A Russian. archaic
Adjective
∙ Of or relating to Muscovy or Moscow, or the people of these places.