adjective. Of, containing, or similar to iron.

adjective. Having the color of iron rust; reddish-brown.

Of the color of iron-rust; light reddish brown.

Of the nature of or containing iron.

adjective. Partaking of iron; containing particles of iron.

adjective. Resembling iron rust in appearance or color; brownish red, or yellowish red.

adjective. Containing iron.

adjective. Rusty.

"Much more recently the idea of ferruginous particles has been revived, their presence being ascribed not to volcanoes, but to the meteorites constantly being dissipated in the upper atmosphere."

ferruginous hawk  

alluvial  argillaceous  ash-colour  auriferous  calcareous