ferruginous

from The Collaborative International Dictionary of English v.0.48

Ferruginous \Fer*ru"gi*nous\ (f[e^]r*r[udd]"j[i^]*n[u^]s), a.
   [L. ferruginus, ferrugineus, fr. ferrugo, -ginis, iron rust:
   cf. F. ferrugineux. See {Ferrugo}.]
   1. Partaking of iron; containing particles of iron. --Boyle.
      [1913 Webster]

   2. Resembling iron rust in appearance or color; brownish red,
      or yellowish red.
      [1913 Webster]