Description
Detailed Description
One of the most aesthetic and distinctive specimens in the lot, this is a three-dimensional “tree” of 90-degree branches of acanthite (a pseudomorph after argentite). The crystal terminations are well defined and there is good separation between the “branches,” giving the overall form some real definition. It is a floater with no point of attachment. In excellent condition, one “branch” is missing – you can display this to the front or the rear, but for me this specimen is actually best displayed with it to the front – it is dull in lustre and not at all distracting. It is at lower left in the first photo. The form makes this specimen – it’s great!
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 after 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.