Calcite, (after Mimetite; w. Duftite)

Size: 53 mm
Owner: Mariusz Oleszczuk
Photographer: Mariusz Oleszczuk

Hollow, tube-like structures composed of white, rhombohedral calcite crystals, and apparently epimorphous after mimetite (?), are richly encrusted (on the outer surfaces) with radiating aggregates of bright-green acicular microcrystals of duftite (XRD verified). The tube structures are completely hollow, with all traces of the original mimetite (?) having been removed (Photograph 3).

Locally, the duftite is overgrown with a brown layer of dolomite and tangeite crystals (XRD verified; see Photograph 2).  A single crystal of dioptase (c. 2 mm) is visible at the extreme bottom left of the specimen (as seen in Photograph 1).

The location in the mine from which this specimen was recovered is not recorded, but it is almost certainly from the second oxidation zone.