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. Etymology. The Northern English/Scots term "whin" is first attested in the fourteenth century, and the compound "whinstone" from the sixteenth. The "Oxford English Dictionary" concludes that the etymology of "whin" is obscure, though it has been claimed, fancifully, that the term 'whin' derives from the sound it makes when struck with a hammer. Description. Massive outcrops of whinstone occur include the Pentland Hills, Scotland and the Whin  Sills, England. 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.