mica

 
Pronunciation: /ˈmʌɪkə/

noun

[mass noun]
  • a shiny silicate mineral with a layered structure, found as minute scales in granite and other rocks, or as crystals. It is used as a thermal or electrical insulator.

Derivatives

micaceous

Pronunciation: /mɪˈkeɪʃəs/
adjective

Origin:

early 18th century: from Latin, literally 'crumb'