These watercolour paintings show the shapes, structures, patterns and remains that mining industry leave upon the land. Sulphide minerals, from coal seams and mineral veins, particularly iron pyrites, are exposed to air and release sulphate and soluble metal ions. The water dissolves metal compounds present resulting in high concentrations of metals, such as iron, zinc, copper, lead, cadmium, manganese and aluminium. The minewaters may be alkaline, acidic, ferruginous, highly saline or clean. When rebounding water reaches the surface it may come out via old adits, springs, seepage through the ground or even through the bed of a river. When it first emerges it often looks clear, because the underground water is low in oxygen and any metals are dissolved. As the water is aerated in a river, iron rapidly oxidises and settles out as an orange deposit of “ochre”. Minewater salinity increases with depth, and in some cases salt deposits near mineworkings can mean that the minewater is more saline than sea water.
For the WordPress Discover Challenge The Things We Leave Behind