azurite (on bayldonite)

TSNB681
Specimen
Palache, C.
Exhibit 1. Azurite (on bayldonite); 105 mm.
Exhibit 1. Azurite (on bayldonite); 105 mm.
Image Credit: Malcolm Southwood
Exhibit 2. 22 mm field of view.
Exhibit 2. 22 mm field of view.
Image Credit: Malcolm Southwood
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Specimen Title

azurite (on bayldonite)

Associated Minerals

bayldonite; conichalcite-duftite (?)

Principal Mineral

Azurite

Size

Cabinet; 105mm

Location in the Mine

First oxidation zone

Provenance

Palache, C

Collection

MGMH; 87484a

Entry Number

Specimen; TSNB681

Description

Equant, lustrous, blue-black azurite crystals (to 5 mm) scattered on a lawn of crystallised Cu/Pb arsenates (not analysed). The matrix consists of extremely dense, but slightly cavernous, massive arsenates with a little azurite


The display surface is a shallow vug lined with a gently mamillated surface comprising composite crescent-shaped microcrystals (to circa 0.3 mm) of slightly bluish-green bayldonite (EDS verified; Frank Keutsch, Harvard University 2025; Exhibit 2. A much less abundant pistachio-green arsenate with minute spindle-shaped crystals is provisionally identified as conichalcite-duftite (?).


The specimen is from the collection purchased by Charles Palache during his visit to Tsumeb in April 1922, which dates it to the upper part of the first oxidation zone (i.e. 8 Level or above).