Southern Uplands Greywacke was sourced from numerous quarries in the Southern Uplands massif, in the counties of Ayrshire, Berwickshire, Dumfriesshire, Kirkcudbrightshire, Lanarkshire, Midlothian, Peebleshire, Selkirkshire and Wigtownshire. The stone consisted originally of muddy sand that was deposited on the sea floor during the Ordovician and Silurian periods (c. 450 million years ago), when Scotland was south of the Equator at roughly the same latitude as northern Angola is today. The terms 'whin' and 'whinstone', which are more usually used to refer to dark grey igneous rocks, have sometimes been used to refer to Southern Uplands Greywacke, because the stone is similarly dense, hard and dark. Some of the stone breaks preferentially along parallel bedding planes, forming blocks of hard, durable stone. Southern Uplands Greywacke was used locally, mainly to form masonry and paving. Southern Uplands Slate, which is relatively mud-rich and breaks readily into thin plates suitable for roofing, is a distinctive variant of Southern Uplands Greywacke. Southern Uplands Slate has been quarried in many parts of the Southern Uplands massif, notably around the villages of Cairnryan (Wigtownshire), New Galloway (Kirkcudbrightshire) and Stobo (Peebleshire). Southern Uplands Slate was used locally, for roofing. Southern Uplands Greywacke and Southern Uplands Slate are not quarried for building stone today.

Building Stone ID 10,088