Memsseedite
Memsseedite is a rare, naturally occurring mineral that was first discovered in the Mems mine in the Democratic Republic of the Congo. It is named after the mine where it was found, and its chemical composition is (Fe,Mn)2(AsO4)(SO4)(OH)2·6H2O. Memsseedite crystallizes in the monoclinic crystal system and typically forms prismatic crystals or granular aggregates. It is often associated with other minerals such as olivenite, mimetite, and wulfenite.
The mineral exhibits a bright yellow to orange color, which is characteristic of its iron and manganese
The mineral's formation is thought to be related to the oxidation of arsenic-bearing minerals in the presence