IRONSTONE CONCRETION - Sahara Desert, Morocco

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IRONSTONE CONCRETION

Sahara Desert, Morocco

In unconsolidated sedimentary rocks iron is often dissolved in the groundwater and can be redeposited as hard, insoluble layers of iron oxide. Round or angular concretions are sometimes formed, consisting of concentric layers of iron minerals such as limonite and goethite.

In this case the concretion consists of layers of varying hardness which have been picked out by erosion.

A curious item. One for the collector of unusual works of nature!

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Size: approx. 10 x 9 x 4 centimetres
Weight: 481 grams