Malachite

Malachite from Cloncurry, Queensland, Australia, measuring 65 × 55 × 42 mm and weighing 186 grams. This is a regional locality specimen from an area well represented in Australian copper collections. Its broad, three-dimensional measurements give a practical sense of scale and distinguish it from thin Malachite coatings or small fragments.

Malachite is a secondary copper carbonate hydroxide. It commonly forms as copper-bearing material alters and copper is redistributed in the presence of carbonate-bearing solutions. Its chemistry provides a useful contrast with copper oxides and sulphides, making the species an accessible starting point for understanding the different mineral forms in which one metal can occur.

Deep green mineral development follows an uneven, pitted surface, with occasional reddish-brown areas interrupting the colour. The small recesses create a varied relief rather than a uniform coating. This is a piece to examine across its whole face, letting the changes in texture and the deeper green hollows reveal themselves gradually. The provenance includes the David Vince and Ruth Coulsell collections. Those names supply the more personal part of the specimen's history, alongside its Queensland origin. For a collection of Australian secondary copper minerals, the piece contributes a substantial Malachite example and an established collecting connection, giving a familiar mineral a defined place in a broader regional account.