Wickmanite is a rare manganese tin hydroxide and a member of the Schoenfliesite Group. It forms isometric (octahedral), brown-yellow, vitreous to resinous, translucent, crystals. It occurs as a late stage, low-temperature mineral at the type-locality: Langban, Filipstad, Varmland, Sweden. Other notable localities include: El Hamman fluorite deposit in central Morocco; in nepheline syenite pegmatite at Heia quarry near Larvik, Norway; and at Pitkaranta, Karelia, Russia. It was named in 1965 for Frans Erik Wickman, a Swedish mineralogist.
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