Chamarel coloured earth

Seven Coloured Earths
Terres des Sept Couleurs

The Seven Coloured Earths are a geological formation and prominent tourist attraction found in the Chamarel plain of the Rivière Noire District in south-western Mauritius. It is a relatively small area of sand dunes comprising sand of seven distinct colours (approximately red, brown, violet, green, blue, purple and yellow). The main feature of the place is that since these differently coloured sands spontaneously settle in different layers, dunes acquire a surrealistic, striped colouring. Another interesting feature of Chamarel's Coloured Earths is that the dunes seemingly never erode, in spite of Mauritius' torrential tropical rains.

The geological formation is a prominent tourist attraction found in the Chamarel plain of the Rivière Noire District in south-western Mauritius. It is a relatively small area of sand dunes comprising sand of seven distinct colours (approximately red, brown, violet, green, blue, purple and yellow). The main feature of the place is that since these differently coloured sands spontaneously settle in different layers, dunes acquire a surrealistic, striped colouring. Another interesting feature of Chamarel's Coloured Earths is that the dunes seemingly never erode, in spite of Mauritius' torrential tropical rains. Since the earth was first exposed, rains have carved beautiful patterns into the hillside, creating an effect of earthen meringue.

The sands formed from the decomposition of volcanic rock (basalt) gullies into clay, further transformed into ferralitic soil by total hydrolysis; the two main elements of the resulting soil, iron and aluminium, are responsible for red/anthracite and blue/purplish colours respectively. The different shades of colour are believed to be a consequence of the molten volcanic rock cooling down at different external temperatures (hence rates), but the causes of their consistent spontaneous separation are yet to be fully clarified.

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