PART OF A SEPTARIAN NODULE (CUT AND POLISHED) - Holderness Coast, Yorkshire
« backPART OF A SEPTARIAN NODULE
Cut and polished
Holderness coast, Yorkshire
A delightful cut and polished piece of a septarian nodule. It is polished on all sides. It is derived from the boulder clay and was brought south to Yorkshire by an ice sheet during the Ice Age.
Septarian nodules, or 'septaria', are remarkable natural objects. They are round concretions containing a network of internal cracks that have been filled with minerals, particularly brown and yellow calcite. No traces of the cracks are visible on the surface of the nodule.
The cracks are called ‘septa’ from the Latin word septum or ‘partition’, which gives the nodules their name. Exactly how these nodules were formed is still not fully understood.
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Size: approx. 7 x 5 x 1 centimetres
Weight: 117 grams