Anglesite with Cerussite

Anglesite with Cerussite from the Kintore Open Cut, Broken Hill, N.S.W., Australia, measuring 50 × 44 × 38 mm and weighing 242 grams. A dense little specimen of two secondary lead minerals that tell a different part of the Broken Hill story to the manganese silicates elsewhere in this sale.

Anglesite, lead sulfate, and Cerussite, lead carbonate, are both products of the weathering of Galena, the lode's primary lead ore mineral, in the oxidised zone nearer the surface. As groundwater and oxygen worked on the Galena, lead was released and recombined first as sulfate and then, as conditions shifted further, as carbonate, so finding the two together is a direct record of that alteration continuing in stages rather than stopping at a single mineral. The Kintore Open Cut exposed a good deal of this oxidised material during its working life, making it a reliable source of secondary lead species for collectors.

Where the Rhodonite and Bustamite in this sale come from the deposit's metamorphosed host rock, Anglesite and Cerussite come from much later, near-surface weathering of the ore itself, two very different chapters of the same mine's geology. This piece is from the David Vince Collection.