lammerite (w. chalcanthite and anhydrite)

A shard of tennantite-rich sulphide ore, partly encrusted with bright blue chalcanthite crystals. Beneath the chalcanthite (which has been partly removed on this specimen) are radial sprays of very dark green - almost black - sub-mm lammerite crystals (Exhibit 2), associated with fibrous, pale green microcrystals of anhydrite. 

The specimen was formerly in the collection of Bill Pinch (Exhibit 3), who obtained it from TCL mineralogist John Innes. Innes' handwritten label (Exhibit 4) indicates that it was collected in the North East Stope on 35 Level in 1980. This discovery is documented by Keller (1981) and by Keller and Bartelke (1982).

Pinch's label records the presence of leightonite but it is hard to discern visually and has not been verified on this specimen, although it is known to occur in this paragenesis (Keller and Bartelke 1982).

"JI-405" penned on the Innes label (Exhibit 4) refers to an entry in the unpublished catalogue of the Innes Collection, prepared by Ernie Nickel in the early 1990s. Nickel's description reads: "Black sulphidic ore topped by a layer (up to 10 mm thick) of bright blue, massive chalcanthite. Minor pale green anhydrite fibres, mainly on chalcanthite-matrix interface. Several small clusters of dark green lammerite crystals (up to 1 mm)."

anhydrite; chalcanthite; leightonite (?); quartz; tennantite-(Zn