A pair of large acanthite crystals (pseudomorphs afte argentite) in parallel growth, the largest measuring 2.9 cm across (!). The piece is a floater with no point of attacment, and is fully crystallized, with the front being well defined, while the back and one side are less so. This is a lot of acanthite – it has some heft! With magnification, minor silver wires are visible in the gap between the two crystals and in another hollow – these appear to be at least partially pseudomorphed by acanthite. In excellent condition – a couple of small rubs on the piece but the tips and edges are well defined without chips or nicks. Great acanthite – due to its size, the overall shape stands out nicely in the cabinet.
About These Acanthites
Well-crystallized acanthite has never been common and most of the known localities for crystals are historic, making it difficult, and usually expensive, to obtain fine specimens. The finds at Imiter (Africa’s largest silver mine) in recent years have placed it among the world’s best localities for crystallized acanthite. Although these crystals formed as argentite, argentite is not stable below 179C, at which point it changes to monoclinic acanthite. The specimens are acanthite pseudomorphs atfer argentite, retaining the isometric crystal form of the original argentite crystals. I assembled this lot of acanthites over a period of about two years. Most of these specimens, from the 2008 find, remained in Morocco until 2013.