The Collaborative International Dictionary of English v.0.48:

Autunite \Au"tun*ite\, n. [From Autun, France, its locality.]
   (Min.)
   A lemon-yellow phosphate of uranium and calcium occurring in
   tabular crystals with basal cleavage, and in micalike scales.
   H., 2-2.5. Sp. gr., 3.05-3.19.
   [Webster 1913 Suppl.]