gossan

[ gos-uh n, goz- ]
/ ˈgɒs ən, ˈgɒz- /

noun

a rust-colored deposit of mineral matter at the outcrop of a vein or orebody containing iron-bearing materials.

Origin of gossan

1770–80; orig. dial. (Cornwall) < Cornish, derivative of gōs blood; akin to Welsh gwaed
Also called iron hat.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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