Gossan n. (Geol.) Decomposed rock, usually reddish or ferruginous (owing to oxidized pyrites), forming the upper part of a metallic vein. Called also iron hat.
... business," thought I; and I laid it on the table opposite me as I went on with my supper. It was a "gossan" wig, as we call it in our parts; a wig grown yellow and rusty with age and wear. It looked so sly and wicked as it lay there, and brought back the events of the day so sharply that a queer dread took me of being discovered with it. I pulled ... — Noughts and Crosses • Arthur Thomas Quiller-Couch
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