biotite

A dark brown to black mineral of the mica group, commonly found in igneous and metamorphic rocks.

• 🇵🇹Mineral escuro, geralmente preto ou castanho-escuro, do grupo das micas, comum em rochas ígneas e metamórficas.

1. Dark mica mineral C1 formal scientific

   A common dark brown to black sheet silicate mineral belonging to the mica group, typically found in igneous and metamorphic rocks.

   • Biotite is often identified by its perfect basal cleavage and dark color.
   • The granite sample contained visible flakes of biotite.
   • Geologists use biotite for radiometric dating of rocks.

   🇵🇹Mineral escuro de mica

• biotites plural form
• biotites' possessive plural form
• biotite's possessive singular form