Definition of penninite in English:

penninite

noun

Mineralogy
  • A green or greenish-blue mineral consisting of a hydrous silicate of magnesium, ferrous iron, and aluminium, and now usually regarded as a pseudo-trigonal variety of clinochlore.

Origin

Mid 19th century; earliest use found in James Dana (1813–1895), geologist, zoologist, and teacher. From German Pennin pennine + -ite. Apparently intended as an alternative term to pennine.

Pronunciation

penninite

/ˈpɛnɪnʌɪt/