Gossan

Iron hat is a miners' term for the oxidation zone of a Erzganges. Its name derives from the forth limonite, which " is the most prominent mineral weathering zone ". The original existing river and barytes were transferred and washed away in aqueous solution, so that the quartz is left as the only gait and have enriched the precious metals that are not solvable. In particular, the silver occurs in the weathered zone in part to solid and as a silver sheen.

This weathered zone of the veins ranges from the surface to the cementation zone, which forms a sharp boundary to the deeper, primary transition structure with much lower grades.

Importance for the mining industry

Since in the gossan deposit pending the best parts even up over days, took in the past, the mining here almost invariably its beginning. As long as it was technically manageable, they built it from the open pit, then go to the civil engineering later. The first mining rush in the Ore Mountains came to an end when the rich parts of the Iron hat were mined out after 100 to 200 years.