
Image Credit: Malcolm Southwood

Image Credit: Malcolm Southwood

Image Credit: Malcolm Southwood

Image Credit: Malcolm Southwood




Specimen Title
Austinite (w. dolomite)
Associated Minerals
conichalcite; dolomite
Principal Mineral
Size
Cabinet; 55mm
Location in the Mine
Undetermined
Provenance
Grosch, K.; Bruce, I.
Collection
Southwood, M.; MS2010.126
Entry Number
Specimen; TSNB459
Associated Minerals
conichalcite; dolomite
Description
A vuggy dolostone matrix hosts glassy rhombohedral dolomite crystals which are extensively overgrown by coarse austinite crystals (to 1 mm). The latter are blocky to prismatic in habit with chisel-shaped terminations (Exhibit 2).
Electron microprobe (WDS) analysis has confirmed that much of the austinite is of near end-member composition (exhibits 3 and 4), but with significant variation; zones corresponding to Cu-bearing austinite and Pb-Zn-bearing conichalcite are also present; the mean composition (Exhibit 3) corresponds to a Cu-rich austinite.
The specimen was aquired in 2010 from Ian Bruce who was dispering the collection of Karl-Heinz Grosch. The location in the mine is not recorded.