Image Credit: RRUFF Database Project (Lafuente et al. 2015; RRUFF ID 070114)
Image Credit: RRUFF Database Project (Lafuente et al. 2015; RRUFF ID 070114)
Specimen Title
Bartelkeite
Associated Minerals
chalcocite; germanite; mimetite; renierite
Principal Mineral
Size
Cabinet; 67mm
Location in the Mine
Second oxidation zone (?)
Provenance
Pinch, W.W.
Collection
MGMH; 2020.7.699
Entry Number
Specimen; TSNB521
Description
Macroscopically, this specimen is a bronze-coloured, germanite-rich massive sulphide ore (Exhibit 2). However, it hosts tiny vugs containing well-formed composite crystals of pistachio-green bartelkeite (to 1.5 mm; Exhibit 1), associated with minute transparent prismatic crystals of pale yellow mimetite.
The specimen is from the collection of the late Bill Pinch but neither its earlier provenance nor its location in the mine is recorded. The paragenesis, however, is strongly indicative of the second oxidation zone.
The bartelkeite has been verified by the RRUFF Project (RRUFF ID 070114) using single crystal XRD and electron microprobe analysis; its Raman spectrum is the RRUFF project standard for bartelkeite. It is also the source of material used in the structural characterisation of bartelkeite (Origlieri et al. 2012).
Comprehensive analytical data is available at https://rruff.info/bartelkeite/display=default/ (accessed November 2024).