Cryptomelane, Goethite, Hollandite, Pyrolusite
Eisenzecher Zug mine, Eiserfeld, Siegen, Siegen-Wittgenstein, Arnsberg, North Rhine-Westphalia, Germany
The microstructure of manganese mineralization from Eiserfeld.
Fine-grained, highly porous aggregates of colloform goethite (dark blueish grey), encrusted by cracky, colloform-banded hollandite (light crème grey), cryptomelane (light blueish grey), and also encrusted by fibrous, highly porous palisades of pyrolusite crystals (light crème ...
© Günter Grundmann, Detmold, Germany