PREHNITE & EPIDOTE

ABOUT THE SPECIMEN Aggregate of large, spherical prehnite grown together with prismatic epidote. When these specimens from Mali first hit the market in the mid 2000's, they became a big deal in the collecting world and the gold standard for this mineral combination, and this is easily one of the nicest I've seen. Many specimens were brought onto the market, and there were still hardly ever any with this combination of outstanding aesthetics and size. The color is some of the best of these finds, and when backlit correctly the glow is honeydew melon green. The epidote gives strong balance with the hues and creates a natural base along the bottom. On the backside you can see complete crystals of epidote embedded in between overlapping prehnite spheres, and many of the epidote here are doubly terminated. In fantastic condition, with barely noticeable points of contact on the top. There are also a couple of areas on the back where some epidote crystals were removed from the surrounding prehnite; I wouldn't even consider these damage and they add to the display in a positive way. Comes with a custom lucite base to prop it up and allow it to stand out in a cabinet. Though the base is labeled as Sandaré, this is a well-known misnomer, likely stemming from its status as a "checkpoint" of sorts when bringing specimens from the workings from the diggings further south to the capital of Bamako.   VIDEO   MORE INFO Diakon Commune sits in rolling savannah country of western Mali where diabase intrusions into the local sedimentary sequence generated localized skarn zones - the geological context documented by Rock Currier during a 2006 locality visit and formally published with Demetrius Pohl in the Mineralogical Record (42:231–250, 2011), which also corrected the persistent trade misattributions to "Sandaré" and "Sadiola Hill" that had circulated since the material first appeared. Prehnite crystallized as a calcium aluminum silicate hydroxide in open cavities within the skarn, its apple-green color driven by iron substitution in the aluminum site; epidote developed as the primary matrix phase, with short prismatic crystals providing the scaffolding on which prehnite botryoids grew. A distinct pale blue-green prehnite with clamshell overgrowths and amphibole inclusions also circulates under "Mali" attribution but originates from Matia near Yelimane - a different geological setting producing a visually and mineralogically distinct material that is frequently conflated with Diakon specimens in the trade. Supply has been periodically refreshed by artisanal digging, keeping prices accessible relative to the aesthetic quality the best floaters represent.