dolerite
Diabase (), also called dolerite () or microgabbro,
is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grain ...
stone quarried in the stone quarries (known locally as the 'Quacks') of the
Rowley Hills
The Rowley Hills are a range of hills in the West Midlands county in England. The range comprises Turner's Hill, Bury Hill, Portway Hill and Darby's Hill.West Midlands of the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
, straddling the border of
Rowley Regis
Rowley Regis ( ) is a town and former municipal borough in Sandwell in the county of the West Midlands, England. It encompasses the three Sandwell council wards of Blackheath, Cradley Heath and Old Hill, and Rowley. At the 2011 census, the com ...
and
Dudley
Dudley is a large market town and administrative centre in the county of West Midlands, England, southeast of Wolverhampton and northwest of Birmingham. Historically an exclave of Worcestershire, the town is the administrative centre of the ...
. The main quarry was on Turner's Hill, and in the 1960s was, in fact, two separate quarries, the Edwin Richards and Hailstone quarries, with a road between them leading to the top of the hill. At that time, hexagonal pillars similar to those of the Giant's Causeway in Ireland could be seen on one of the quarry faces. The Edwin Richards quarry was combined with the Hailstone quarry by removing the disused road between them. It remained active until 2008, operated by Midland Quarry Products. During the 1980s and 1990s,
The Rowley dolerite is an intrusion of late Carboniferous age in the form of a
lopolith
A lopolith is a large igneous intrusion which is lenticular in shape with a depressed central region. Lopoliths are generally concordant with the intruded strata with dike or funnel-shaped feeder bodies below the body. The term was first defin ...
. The country rock consists of the Etruria Marl Formation.
The main use of the Rowley Rag stone was in the production of road surfaces and kerbstones.
A
public house
A pub (short for public house) is a kind of drinking establishment which is licensed to serve alcoholic drinks for consumption on the premises. The term ''public house'' first appeared in the United Kingdom in late 17th century, and wa ...
in the village of Whiteheath was named after this rock, highlighting the importance of this naturally occurring product in this area of the Black Country.
William Withering
William Withering FRS (17 March 1741 – 6 October 1799) was an English botanist, geologist, chemist, physician and first systematic investigator of the bioactivity of digitalis.
Withering was born in Wellington, Shropshire, the son of a surg ...
, a member of the
Lunar Society
The Lunar Society of Birmingham was a British dinner club and informal learned society of prominent figures in the Midlands Enlightenment, including industrialists, natural philosophers and intellectuals, who met regularly between 1765 and 1813 ...
, studied the chemical composition of Rowley Rag and gave a paper including this study to the
Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...