AMYGDALOIDAL BASALT (CUT AND POLISHED) (GLACIAL ERRATIC) - Holderness, Yorkshire

AMYGDALOIDAL BASALT (GLACIAL ERRATIC)

Cut and polished slice of basalt containing tiny colourful agates. 

Glacial boulder clay.  Holderness Coast, North Yorkshire

A good example of basalt lava with tiny crystal-lined cavities known as amygdales (former gas bubbles in the molten lava).  The cavities are lined with colourful agate.

It was recovered from glacial boulder clay on the Yorkshire coast. Brought to Yorkshire from Fife in Scotland by an ice sheet 20,000 years ago.

This is a slice that has been polished on both sides. An interesting specimen.

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