Aurichalcite, (w. Hemimorphite and Hydrozincite)

Chemistry: (Zn,Cu2+)5(CO3)2(OH)6
Size: 63 mm
Owner: Malcolm Southwood
Photographer: Malcolm Southwood

Needles of turquoise-blue aurichalcite, and flattened, colourless blades of hemimorphite (both XRD-confirmed), line an open vug in a pinkish-tan coloured rock matrix. FOV for the close-up photograph is c. 22 mm.

Earthy, but bright-white, massive hydrozincite(?) is partly encrusting both of these minerals within the vug, and is also abundant all over the matrix, locally forming micro-botryoidal textures.  Note that the hydrozincite has not been verified by analysis; however, this assemblage is a well-documented one (see Gebhard, 1999).  The specimen almost certainly originates from very high in the first oxidation zone, possibly from the outcrop or the open pit.