The Collaborative International Dictionary of English v.0.48:

Ilvaite \Il"va*ite\, n. [From L. Ilva, the island now called
   Elba.] (Min.)
   A silicate of iron and lime occurring in black prismatic
   crystals and columnar masses.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Yenite \Ye"nite\, n. [After Jena, in Germany.] (Min.)
   A silicate of iron and lime occurring in black prismatic
   crystals; -- also called ilvaite. [Spelt also jenite.]
   [1913 Webster]