Artist paints a green future for coal mine sludge with pigment creation

Onya McCausland’s ‘Six Bells Red’ line of pigments has been launched at the Coal Authority’s Six Bells mine water treatment scheme in South Wales

An innovative artist has demonstrated a new way to use ochre from treated mine water by using the product in fine art paints.

Onya McCausland from the Slade School of Fine Art at University College London (UCL) created the ‘Six Bells Red’ limited edition line of wall paint and artists’ oil paints, when studying for her doctorate, which has been launched at the Coal Authority’s Six Bells mine water treatment scheme in South Wales.

The Coal Authority manages 82 mine water treatment schemes across Britain, handling and treating more than 122 billion litres of mine water every year.

The schemes prevent up to 4,000 tonnes of iron solids from entering watercourses – if the water is left untreated, it could pollute and stain the riverbed turning it orange.

Ms McCausland visited former coal mine sites across Britain where she collected samples of ochre for further study and through her paintings, discovered striking differences between the pigments depending on their geographical location.

Working with chemists from UCL and the Coal Authority, she carried out various trials on the ochre – it was milled and burnt, examined under electron microscopes and subjected to light fastness tests to fully develop the potential of each colour.

Six Bells Red contains more than 50% of iron and is a deep reddish hue.

It is one of a number of ways the Coal Authority is looking at recycling ochre that is removed from mine water during its treatment process.

Jon Aumonier, the Coal Authority’s Innovation Project Manager said: “Onya’s use of ochre from our mine water treatment schemes in this project is just one of the rewards of the hard work and financial commitment made by the Coal Authority in the recovery, process and testing of ochre samples.

“We have worked very hard to get the ochre to this point and seeing it turned into pigments is fantastic.”

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