KÖTTIGITE on NATIVE ARSENIC

SPECIMEN DESCRIPTION

This is a very rare, but richly crystallized specimen of cobalt-rich Köttigite from Antonsthal in Erzgebirgskreis, Saxony, Germany. As a hydrated zinc arsenate Köttigite should be really be colourless but is rarely so, being coloured by a range of trace elements as impurities - pink being the result of cobalt. This small cabinet-sized specimen is unlikely to be placed on display, but is very rich, consisting of a matrix of Native Arsenic within which extensive cavities are lined with secondary pale pink silky microcrystals and sprays of Köttigite. Under magnification the crystals are beautiful. Interestingly, the Type Locality for Köttigite is seven miles to the northwest at Daniel mine, Neustädtel, where it is also pink coloured. From the superb systematic collection assembled by the brothers Martin and Michael Günther (1951-2007 & 1956-2021).