Whinstone

Whinstone is a term used in the quarrying industry to describe any hard dark-coloured rock. Examples include the igneous rocks, basalt and dolerite, as well as the sedimentary rock, chert.

Massive outcrops of whinstone occur include the Pentland Hills, Scotland and the Whin Sills, England.

The name 'whin' derives from the sound it makes when struck with a hammer. It is used for road chippings and dry stone walls, but its natural angular shapes do not fit together well and are not easy to build with, and its hardness makes it a difficult material to work. A common use is in the laying of patios and driveways in its ground/by product state called Whindust.

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