hiddenite

/ˈhɪdənaɪt/
noun
  1. A rare green gemstone, a variety of spodumene, named after the mineralogist W.E. Hidden.
    • She added a hiddenite pendant to her collection of rare gems.
    • Hiddenite is found mainly in North Carolina and is prized by collectors.
    • The jeweler displayed a beautiful hiddenite ring in the window.