Manganese ore lense - Rammelsberg, Harz Mts

Polished black manganese lense from the world heritage ore mine of Rammelsberg with finely dispersed sparkling pyrite and a well-contrasting white calcite core. The lense is held by a peculiarly organic looking black tube with pyrite in it, too. 

Size: 10,5 x 6,2 x 5,5 cm

Locality: Rammelsberg, Goslar, Lower Saxony, Germany