NS3678 : Former cornstone workings on Carman Muir

taken 13 years ago, near to Renton, West Dunbartonshire, Great Britain

Former cornstone workings on Carman Muir
Former cornstone workings on Carman Muir
On satellite views, this area is quite distinctive. It consists of a long straight pit, with well-defined edges, stretching about 50 metres from NNE to SSW, with a couple of smaller continuations leading SSE and WSW from the south-western end of the main pit. It is located at the centre of the following satellite image; the area is shaped like a capital Y with a long tail, but it may or may not be apparent, depending on the current satellite imagery: LinkExternal link

It is located on a west-facing slope, the land gently rising to a wide summit area less than 100 metres to the east of this point. The pit contains several large mounds of stone, as shown here. Although not shown in this photograph, the places where the stone has been quarried can be seen in several places along the edge of the pit; a few other sites of excavation can be found nearby, such as NS3678 : Pit from former limestone quarrying.

A fellow contributor brought to my attention a relevant article by naturalist John Mitchell: "Old Cornstone Workings in Dunbartonshire and West Stirlingshire, with Notes on their Associated Flora" ("Glasgow Naturalist", Volume 22(5), 1995, pp485-494).

According to that article, cornstone, which has the alternative name caliche, is a terrestrial rather than a marine limestone. It was burned to produce lime for use in the cultivation of cereal crops; this was a folk industry rather than a large-scale commercial venture, and the practice rapidly tailed off after the start of the nineteenth century.

The article lists several former cornstone workings, including one at Kipperoch (NS 368 783), corresponding to the site shown in my photograph. The article also mentions the remains of a lime kiln, which I did not locate until later: Link

As the same article explains, former cornstone workings are of ecological importance because the calcium carbonate leached from the rocks gives rise to a less acidic habitat, which can support various plant species that would not otherwise occur in the area (the lime-enriched habitat here is rather different from the surrounding area, which consists, in general, of fairly acidic heathland).

In the background, on the other side of the River Clyde, the area around Port Glasgow and Gourock is visible.
Old cornstone workings

Cornstone (a kind of limestone) was quarried from various locations on Carman Muir, to be burned for lime, but the industry was centred on this particular knoll: a ruined lime-kiln can be seen on its northern side, and there are extensive spoil mounds and signs of quarrying nearby. See LinkExternal link for an annotated satellite view centred on this area. See Link for details of former quarrying on Carman Muir as a whole.

Carman Muir: outcrops and old quarry pits :: NS3778

See Link (in a Geograph article) for further information, and LinkExternal link for an annotated satellite view on which various features of geological interest (as well as traces of associated industries and other antiquities) are marked, as described below.

The topography of the parts of Carman Muir to the south of Cardross Road is determined to a large extent by cornstone deposits, which outcrop in places. Cornstone is an impure granular limestone, a fossil soil. Old quarry pits (probably worked before the nineteenth century) and possible test pits can be seen along the lines of these deposits; they are indicated by light blue marker pins on the annotated satellite view, and the cornstone outcrops are marked by orange pins.

This area, lying to the south of Cardross Road, exemplifies what the British Geological Survey refers to as the Kinnesswood Formation (see LinkExternal link at the BGS website for more information); this formation contains cornstone deposits.

Beside and to the north of Cardross Road are outcrops of sandstone rather than cornstone. The sandstone is best seen along a line of outcrops and pits beside the road (these are indicated by reddish marker pins on the annotated satellite view). Another prominent example lies at the ENE end of that line: a large disused red sandstone quarry, the old Fairy Knowe Quarry (later known as Carman Quarry) Link at NS36967900. This area beside and to the north of the road exemplifies the Stockiemuir Sandstone Formation (see LinkExternal link at the BGS website for further details).

Both north and south of the road, the strata in this area generally dip at an angle of from 10 to 20 from the horizontal, descending towards the SSE; the Stockiemuir Sandstone Formation that is exposed beside and to the north of the road underlies the cornstone-containing Kinnesswood Formation to the south of the road.

The annotated satellite view also includes markers for various antiquities in the area:

● Ancient cairns: Link
● Circular enclosure: Link (originally reported as a hut circle)
● Carman (house): Link
● Carman (enclosure): Link
● Carman (field system): Link

Creative Commons Licence [Some Rights Reserved]   © Copyright Lairich Rig and licensed for reuse under this Creative Commons Licence.
1:50,000 Modern Day Landranger(TM) Map © Crown Copyright
1:50,000 Modern Day Landranger(TM) Map © Crown Copyright
TIP: Click the map for Large scale mapping
Change to interactive Map >
Grid Square
NS3678, 137 images   (more nearby search)
  (find more nearby)
Date Taken
Monday, 23 February, 2009   (more nearby)
Wednesday, 25 February, 2009
Geographical Context
Quarrying, Mining  Derelict, Disused 
Place (from Tags)
Carman Muir 
Period (from Tags)
18th Century 
Quarry   (more nearby)
Subject Location
OSGB36: geotagged! NS 3683 7835 [10m precision]
WGS84: 55:58.2202N 4:36.9654W
Camera Location
OSGB36: geotagged! NS 3685 7835
View Direction
WEST (about 270 degrees)
Looking for a postcode? Try this pageExternal link
Clickable map

Other Tags
Limestone  Cornstone 

Click a tag, to view other nearby images.

Image classification(about): Geograph
This page has been viewed about 350 times.
View this location: KML (Google Earth) · Google MapsExternal link · Bing MapsExternal link · Geograph Coverage Map · geotagged! More Links for this image
W Go E
thumbs up icon
You are not logged in login | register