biotite

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

• 🇷🇺Темно-коричневый или черный минерал из группы слюд, обычно встречающийся в магматических и метаморфических горных породах.

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.

   🇷🇺Темный слюдяной минерал

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