Site 2: Cornish Metals

Cornish Metals

South Crofty Mine, Dudnance Ln, Pool, Redruth TR15 3QT

Orange Ochre - Iron oxide, organic flocculant, traces of arsenic 

At this facility (which cost £7 million pounds) water is being pumped out of the mine tunnels and purified. This is so that the mine can be reopened for further tin ore extraction. It is first mixed with hydrogen peroxide, and then with lime. After this, an organic flocculant is added to stop the sludge from forming too thickly at the bottom of the silos. The chemical additives change the Ph of the water so that it is within 7-8 and removes toxic heavy metals. The change in Ph pulls the dissolved minerals out of suspension so that they precipitate into solids. The ochre sludge is then pumped back into parts of the mine that won’t be used.

Dried iron oxide

Wet iron oxide

Waste mine water processing plant, waste product iron oxide sludge

Laid out in enamel trays for dehydration

Iron oxide drying 

Iron oxide sample calcined (burnt) to 10 different temperatures which creates different colours & associated properties. 

Iron oxide pigment mixed with linseed oil to maker paint with a glass muller & plate.