Danaite is a rare Co-bearing variety of arsenopyrite, originally described from Franconia, Grafton Co., New Hampshire, USA. Named after James Freeman Dana, a well-known chemist and mineralogist, instructor at Harvard University.
Here is a fine classic specimen from Skuterud Mines, Modum, Buskerud, Norway. These were former Co-Cu mines operated from 1778 until 1898. The specimen is hosting serveral bright silvery crystals of danaite up to 6 mm frozen in matrix, associated with golden chalcopyrite.

Comes with two old labels in the writing of A. A. Damour and on-glued corresponding number sticker. His personal mineral collection was sold to F. Krantz (who was in charge of the Krantz mineral dealership between 1891 and 1926), probably shortly after his death.

Modum is situated in present norway and not in sweden as the label states. In 1814, after being on the losing side of the Napoleonic Wars with Denmark, Norway was ceded to the king of Sweden by the Treaty of Kiel. Norway declared its independence and adopted a constitution. However, no foreign powers recognized the Norwegian independence but supported the Swedish demand for Norway to comply with the treaty of Kiel. The union with Sweden was dissolved in 1905.

'Mispickel' is an old synonym for arsenopyrite.