Geological Survey of Great Britain. Wartime pamphlet no. 21. - Ochres, umbers and other natural earth pigments of England and Wales

By R.W. Pocock

Introduction

Natural mineral pigments include such materials as ochres, umbers and siennas (Ladoo, 1925). Some pigments are made by mixing natural mineral pigments with chemically manufactured pigments, and in the preparation of mixed paints for use it is customary to mix two or more pigments together to produce a paint with the specific colour and properties desired.

The classification of pigments by colour is somewhat indefinite and confusing as the same name is often used to apply several distinct materials both natural and artificial.

Mineral Reds:- Most of the mineral reds derive their colour from the presence of varying amounts of ferric oxide (Fe203), the mineral haematite. This may be present in relatively small percentages, as in red slates and shales, or it may constitute as much as 90 percent or more, as in Spanish Red. In an intermediate position come various types of bole, ruddle or reddle, a ferruginous, non-plastic red, yellow or brown clay. The red oxide may occur naturally or it may be produced by heating hydrous iron oxide pigments, such as yellow ochres, or iron carbonate ores, to a high temperature.

Yellows:- Yellow Ochre is the only important natural mineral yellow, and has been used since prehistoric times. It is known by many names, including Mineral Yellow, Permanent Yellow, Stone Yellow, Roman Ochre, Roman Earth, Oxford Ochre, Chinese Ochre, Golden Ochre, etc. It consists essentially of a mixture of clay, siliceous matter and hydrated iron oxide (limonite). The iron oxide content varies from 15 to 30 percent or more.

Greens:- Green Earth, terre verte, green ochre, Celadon green, Verona green, etc. is a decomposition product of basaltic tuffs. No occurrences are worked in this country but green earth is present in the amygdaloidal toadstones of Derbyshire and similar rocks elsewhere.

Blues:- There are not natural mineral blues now in use. The mineral lapis lazuli, ground to form a deep-blue pigment, was once highly valued but has now been replaced by artificial ultramarine.

Browns:- Sienna is a high-grade natural yellow-brown earth pigment consisting of a mixture of hydrous iron oxides and clays in varying proportions, with or without siliceous matter. It may contain a little manganese dioxide. It grades into ochre with decreasing iron oxide content and into umber with increasing manganese oxide content. It usually is higher in iron oxide than ochre (often 60 to 80 percent) and therefore stronger and richer in colour. The colour often varies from pure-brown to reddish-brown.

Burnt Sienna, made by calcing raw sienna, varies in colour from a pure-brown to a bright red.

Umber:- consists of a mixture of clay, hydrous iron oxide, manganese oxides, organic matter and sometimes siliceous matter. It usually contains from 7 to 14 percent manganese dioxide and often 50 per cent ferric oxide. It is a darker shade of brown than sienna.

Burnt umbers:- made by calcining umbers, have deeper and richer shades that the raw earths.

Other natural brown pigments:- are obtained from bog earth, peat or lignite deposits and are essentially mixtures of clay or ochre with varying proportions of bituminous matter.

Blacks:- In nearly all black pigments the colour is derived from some form of carbon, but impure black oxide of manganese ‘wad’ has been mined principally in Derbyshire, and used for paint. A printing ink based on crude manganese dioxide has the advantage of being readily bleached by treatment with a little sulphur dioxide.

Most of the occurrences listed below, numbered according to the Sheets of the ‘New Series’ one-inch map of England and Wales (see Frontispiece), either are or have been worked. In addition there are other deposits which might be exploited as a source of pigments. Of these the most promising are the weathered outcrops of the Northampton Ironstone (sheet 157), from which a large percentage of good yellow ochre could be separated. The waste dumps of fines from the clamps, in which this ore has been calcined, contain a considerable proportion of a red ochre. Red ochre could also be produced by calcining and grinding the raw ore.

Experiments carried out by Mr C. O. Harvey on a sample of iron carbonate ore from the Top Block of the Cleveland Ironstone of Eston (Sheet 34) show that a range of colours, depending on the degree of heating, can be obtained. It appears that the colour of pigments obtained by roasting iron salts depends on the time and temperature of roasting. Metallic impurities, such as manganese, also have their effect on the colour. The same influences may be expected to affect the colour of the product obtained by heating ferrous carbonate, and some variation in colour may be caused by the degree of completeness of oxidation. It may be that an incompletely oxidized powder will not be sufficiently stable for use as a pigment.

The material used for ignition experiments on the Cleveland Ironstone was roughly graded to an average diameter of about 2½ millimetres and, after heating, was powdered. The range of tints obtained was a follows:-

0°	greenish grey
250°	yellowish green
300°	greenish yellow
400°	dull orange
500°	reddish orange
600°	brownish orange
700°	reddish brown
900°-1000°	brownish red

In each case the time of heating was about 2 hours.

More brilliant colours might be obtained by modifying the method of treatment (e.g. by moistening with ferrous sulphate, by heating in a current of steam, etc.), but economic factors would probably operate the adoption of such processes.

An example of the successful use of an iron carbonate ore such as a source of pigment, in America, is the Paint Ore of Lehigh Gap, Pennsylvania (Agthe, F, T. and J. L. Dynan, 1910).

This ore, consisting principally of carbonate iron, is calcined and fine ground. The calcined material is very compact and of a dark reddish brown colour.

The paint made by mixing with oil requires no dryer and is very durable under the most severe conditions of exposure.

Yellow ochre has for many years been produced from mine waters in Anglesey (Sheet 93), in Cornwall (Sheet 352) and in certain coalfield areas by deposition in settling tanks. This process might be adopted in other cases where mines are highly charged with iron (Sheets 84, 87, 121).

The mineral glauconite, so abundant in certain sands, could readily be separated out and ground to yield a strong green pigment, but tests would have to be made to determine its permanence and other properties. When calcined, a rich red brown colour is produced. A good example of a highly glauconitic sand is worked in the Bracklesham Beds at Knaphill Brickworks near Woking (Sheet 285).

For much useful information regarding the chief minerals used in the paint industry, whether as pigments, extenders, fillers or suspending agents, reference should be made toa recent paper by the Principal, Mineral Resources Department, Imperial Institute, London (Johnstone, 1941).

The table on p. 4, extracted from the statistics of the Mines Department, shows that the average annual output of ochre and umber, in England and Wales, for the yeas 1919 to 1938 has been slightly in excess of 9,000 tons.

	One- Inch Sheets	1919	1920	1921	1922	1923	1924	1925	1926	1927	1928	1929	1930	1931	1932	1933	1934	1935	1936	1937	1938
Anglesey	93	433	558	496	314	270	395	595	554	560	587	574	300	280	100	300	200	300	380	370	250
Glamorgan	249 262	-	-	-	-	-	-	-	98	182	230	170	165	128	162	152	18	67	25
Cornwall	335-7 346-8 351-3 358	578	452	110	-	221	521	322	210	132	235	253	205	226	1,033	150	13	20	-	100
Derbyshire	86 111-2 124-5	9	588	398	291	400	419	306	440	376	379	208	108	75	18	-	94	46	84	120	59
Devon	277 292-3 337-9 349-50	968	1,295	895	628	1,100	849	1,041	980	929	1,059	1,017	980	1,269	942	1,214	1,072	1,025	918	8936	836
Gloucestershire	233 265	3,143	3,797	2,726	1,965	2,382	1,852	3,118	2,878	2,707	3,216	2,959	2,704	2,119	2,172	2,485	1,521	1,149	929	1,390	)
																					)4,737
Somerset	264 278-9 280 294-5 312	4,418	7,665	5,235	5,838	5,920	6,433	5,842	5,043	5,578	4,798	4,162	4,161	3,267	3,321	4,406	4,475	5,709	4,962	5,194	)
Northumberland	18	-	-	144	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
		9,549	14,355	10,044	9,036	10,293	10,469	11,224	10,203	10,464	10,504	9,343	8,263	7,364	7,748	8,707	7,393	8,316	7,298	8,067	5,882

Occurrences

The following notes on mineral pigment localities are arranged according to One-inch ‘New Series’ Sheets (18, etc.), see Frontispiece. In most cases a locality is referred to the six-inch quarter sheet of the county in which it is situated (e.g. Northumberland 110 N.W.), but here a word of caution is required, since sometimes more than one suite of county six-inch sheets have been issued.

References to the principal published sources of information are given in the ext in abbreviated form, expanded in a list at the end of the pamphlet,

The information furnished regarding pigment occurrences is stated very briefly and in many cases can be supplemented with detail on application to the Director, Geological Survey, Exhibition Road, South Kensington, S.W.7. Any additional facts or corrections supplied by readers will be gratefully added to the Survey File.

18. Slaggyford, N. of Alston

Northumberland 110 N.W. Reference: Trotter and Hollingworth 1932, p. 182.

Ochre has been worked in the Carboniferous Limestone Series in the great and little limestones north of Great Heaplaw and in the latter limestone at Town Green, Slaggyford. Umber, for gas purification, is mined at the horizon of the Little Limestone south of Slaggyford; the output reached 1,000 tons per annum in the period 1915-1917. There appear to be reserves.

23.Caldbeck District

Harestones

Cumberland 47 S.E. 3½ miles S.S.W. of Caldbeck A vein of umber said to be from 3 to 4ft. wide with a central rib of spar has been worked intermittently since 1887. A shaft was sunk 3 fathoms on the vein and the umber carried by aerial ropeway to Roughton Gill, about half a mile to the west, where it was dried and ground.

Drygill

Cumberland 47 S.E. 3½ miles S. of Caldbeck. Black umber has been worked at this locality.

Theifgill. Cumberland 47 S.E. Ochre has been produced here about half a mile upstream from Roughtongill Lead Mine.

24. Horse Edge

Cumberland 33 S.E. Reference: Dunham 1941. The iron ore deposit at Horse Edge is in a vein 66ft. wide in places and has a superficial layer of umber, 0 to 10ft. thick, similar to that at Slaggyford (18).

25. High Teesdale and Weardale

High Teesdale.

Durham 30. Reference: Clough 1903, p. 259.

In the small streams, thin irregular bands of soft, rather siliceous, clay and iron ochre occur. The clay and ochre represents limestone beds in the Carboniferous Limestone Series which have been eatan away along the outcrop and replaced by ‘famp’.

The ‘famp’ in the Yad Moss level, Durham 30 N.W., is moxed with irregular streaks of black earthy mineral, part of which is probably a black ore of manganese. In the West Back and Old Langdon Hushes, Durham 30N.E., S.E., the ‘famp’ consists of nearly pure iron ochre.

Weardale

In Weardale a ‘famp’ of a similar character has been largely worked for smelting. The light yellow varieties of ‘famp’ are sometimes used instead of whitewash, for painting over walls, &c.

29. Glenderamakin (Saddleback Old Mine?)

Yellow ochre and umber have been worked here in the past.

34. Eston, Middlesborough. Yorkshire 16 N.E. Reference: Lampugh and others 1912

The Cleveland Ironstone, a carbonate ore in the Middle Lias, when calcined and ground, yields an ochre of various shades of yellow and red according to the degree of heating (see Introduction). A useful product could no doubt be obtained by careful selection and treatment of the ore from certain horizons and localities.

36. See 46, etc.

43. Ingleby Greenhow

Yorkshire 29 S.W., 43 N.W. Reference: Fox-Strangways 1891, p. 475.

Yellow or brown ochre, formed from the decomposition of the Cleveland Ironstone (Middle Lias), is sometimes found in the neighbourhood of the whinstone dyke, and also occurs in narrow seams and bodules at many places along the Cleveland escarpment. At Rud Scar, near Ingleby Greenhow, there is a seam of red ochre or ruddle, which was formerly used by the farmers for marking sheep.

36, 46, 56, 57. Isle of Man

Reference: Lamplugh 1903

Bradda

Isle of Man 15 N.E. Ballacorkish. Isle of Man 16 N.W.

The production of colouring earths, ochre and umber, in small quantity in the Isle of Man dates back at least from the beginning of the nineteenth century. Macculloch, in 1819, mentions that “yellow ochre has been found in sufficient quantity in some of the mineral veins to have become at one time a matter of export”, but that the mines had long since ceased to be wrought. The mines referred to were probably Bradda and Ballacorkish, as Smyth notes the occurrence of the substance in these lodes.

Rolandsway

Isle of Man 16 N.E.

The upper surface of the Carboniferous Limestone in the low cliffs north of Rolandsway is sometimes decomposed into brown ‘umber’, especially where the limestone is dolomitised.

Booilevane

Isle of Man 5 S.E.

The top of the limestone has probably at one time been excavated in the shallow depression, 700 yds. North of Booilevance, at the place marked Umber Pit on the six-inch map.

Maughold Head

Isle of Man 5 S.E.

The Umber Mine Level, on the southern side of Maughold Head, marked U on the One-inch geological map, was last in operation between 1887 and 1893 and appears to be driven on a decomposed dyke of olivine-dolerite having the usual north-westerly direction.

The total output of ochre, umber, &c. from the Isle of Man for years between 1854 and 1883 is as follows:-

1854 - 164 tons	1870 - 142 tons	1878 - 232 tons
1856 - 151 tons	1871 - 172 tons	1879 - 156 tons
1858 - 120 tons	1872 - 148 tons	1880 - 166 tons
1861 - 116 tons	1873 - 248 tons	1881 - 207 tons
1866 - 130 tons	1874 - 156 tons	1882 - 171 tons
1868 - 149 tons	1875 - 183 tons	1883 - 188 tons
1869 - 139 tons	1877 - 170 tons	There are no returns after 1883.

84. Wigan District

Skelmersdale

Lancashire 92 N.E. Reference: Tonks 1938

On the eastern side of the Skelmersdale Coalfield Triassic Sandston occurs on the downthrow side of the Upholland Fault. Below it occurs red “raddle” over normal coal measures.

In the Prescott Pit, ½ mile S.S.E. of Digmoor (marked “Colly” on the 1 inch map) the following section was proved:-

	Feet	Inches
Drift	28	3
Rough red rock	34	3
Dark red ravin	34	0
Broken ground and steps	15	0
Hard metal or linstrey	11	6
Light ravin	30	0
Red ravin and boulders	31	3
Middle Coal and Measures below	0	0

Local miners describe the red ravin as red raddle, a soft red metal or marl. According to L.H. Tonks it is an ordinary red marl, of Permo-Triassic age, and not comparable with the raddle of Somerset, &c.

Haydock.

Lancashire 101 S.E.

Wood Pit

Messrs. Richard Evans & Co Ltd, Haydock Office, St. Helens. A considerable amount of yellow ochre is precipitated from the waters of this coal pit and some tons could be obtained.

Maypole Colliery

Wigan Lanacshire 93 N.E. The Wigan Coal Corporation Ltd, Wigan

Possible sources of supply for yellow ochre are the outlet from the Haigh Sough (Aspull Water), the Low Hall Pumps and the Taylor Pit Pumps. The ochre is not deposited unless water is exposed to the atmosphere. Tanks or reservoirs for this purpose would have o be installed.

Pumping Pit, when in operation, used to provide large quantities of ochre by tanks, at 5 moor, now abandoned.

The following samples of water have tested:-

	1	2	3
	Ow Hall Pumps	Sough in Plantation	John Pit
Ochre in lbs. Per 1000 gallons	0.14	0.61	0.41
Action on litmus	Neutral	Faintly acid	Neutral

These samples were fairly clear when first drawn, but the ochre settled out in about 48 hours. The above tests were made after settling. According to this there would appear to be about 500 lbs. Per day coming through the Sough which if passed through settling tanks should produce about one ton of ochre per week.

86. Glossop District

Several chalybeate springs in the Millstone Grit area are depositing small quantities of ochre, probably nowhere in workable amount. Perhaps the largest is on Harrop Moss, 2 ¼ miles N.E. of Glossop crossroads, Derbyshire 3 N.W. There may be a ton or more of wet and spongy ochre here,

In the coalfield areas there are small deposits from water-looses in the hills but none workable.

87. Rawmarsh

Westfield Adit

Yorkshire 289 N.E.

Yellow ochre is deposited in colliery adits controlled by the South Yorkshire Mines Drainage Committee. Pumping is under the management of Mr H. Saul of Grange House, Moorgate, Rotherham, who reports that there are several ochreous waters in the district, some of which run through the ironstone measures. One adit was specially driven to drain ironstone mines.

There are large deposits of ochre. Perhaps forty tons are available for immediate working and a continuous supply of one ton a day could be maintained with little difficulty for a considerable period. If arrangements were to be made for resettlement at the outlet this might be considerably increased.

In cleaning adits the method used is that of agitation of the water and the problem is the economics of collecting the ochre. There are several miles of adit which can be utilised.

Mickelbring

Yorkshire 290 N.W. References: J. Walton 1940, A Sedgwick 1835.

Red iron oxide, known as “ruddle”, “reddle” or “raddle”, occurs in the highest Coal Measures beneath Lower Magnesian Limestone. Shafts now overgrown. Worked about 100 years ago

Shafts 23ft. deep and 5ft, in diameter were sunk through the overlying limestone and grit to the 9 inch bed of ruddle which was covered by a 3 ft. bed of clay and underlain by a similar bed. The miner descended by ladder and excavated the ruddle about 4 yds. From the centre until the overburden showed signs of collapse. The ruddle was drawn up by a winch and ground at a mill. It was used for doorsteps, for paint and for marking timber. Sold at about £5 per tin. Large quantities were exported to Holland.

The following section is given by Sedgwick:-

	Feet	Inches
Magnesian Limestone
White and yellow marl	1	6
Yellow rubbly limestone	4	0
Reddle		5
Red and Yellow clay	2	0
Reddle		4
Red and Yellow clay	2	0
Reddle		9
Clay and sandstone	40	0
Coal	1	5
Fireclay

93. Angelsey

Parys Mountain

Angelsey 3 S.W. References: Greenly 1919, Dewey 1925.

Ochre is produced indirectly with copper at the Mona and Parys Mines, Amlwich. The working is almost entirely by solution and precipitation process. Water is pumped up to the top of the hill and allowed to flow into and remain for some time in the old workings, the mine being flooded up to about the deepest parts of the floor of the West Pit; that is to about 300 ft. above sea-level. The waters drain down to a level which slopes towards north and flow for half a mile through a launder to a series of precipitating tanks, made of brick and cement with wooden partitions, at Dyffryn-adda 178ft. above the sea.

The mixed sulphates, which are acid, are treated with scrap-iron, and the copper precipitated as a fine crystalline powder. The water is then pumped into ochre ponds where the ferric hydrate is deposited. The ochre is used for puryifing coal-gas and also in the preparation of pigments, chiefly ‘Venetian Road’. The output of ochre has averaged 300 tons a year.

The water finally passes out to sea and colours it light yellow for some distance from the shore.

Umber appears, at one time, to have been made from the decayed parts of the more ferruginous of the Pre-Cambrian Gwna Limestones. The Later Dykes, too, decompose to an ochreous earth. Possibly the loam found as a solution-residue in fissures in the Carboniferous Limestone might furnish a similar colour.

111. Buxton

Derby 21 N.E.

Ochre is deposited by waters from an old mine level 2 miles south-west of Buxton close to the Macclesfield Road.

Elton

Derby 28 S.E. References: Farey 1811, Green and Strahan 1887.

Wad or black oxide of manganese was worked in the Carboniferous Limestone above the toadstone at Elton. It was prepared at Wensdley (Farey, 1811) as a black pigment for ships and buildings. At Heyspots Mine it was found in layers from six inches to two feet thick resting upon sand blocks of limestone, below which is a pipe of lead ore, and was supplied to the paint maills at Bonsall and Matlock.

Youlgreave

Youlgreave, about a mile south of Middleton. Derby 28 S.W. Reference: Gren and Strahan1887.

Wad has been raised here from a vein in the Carboniferous Limestone and is associated with brown oxide.

Winster

Derby 33 N.E. Reference: Dewey and Dines 28 S.W.

On the Buxton Road, two thirds of a mile out of Winster, wad occurs in flats, pipes and pockets in the Carboniferous Limestone, but so irregularly that it cannot be worked systematically. It occurs with ochre and some barites and has been raised in small quantities and supplie to the Via Gellia colour works at Matlock.

112. Matlock

High Tor Rake Derby 34 N.E. Reference: Green and Strahan 1923.

Some yellow ochre has been raised fron High Tor Rake traversing Carboniferous Limestone.

Yellow and red ochre has been worked at Ashover (Fall Hill), Cromford, and other localities.

Brackenfield. Derby 35 N.W.

Mineral Black has been obtained from a quarry at Lindway Lane, Brackenfield, near Alferton by the Derbyshire Silica Firebrick Co. The bed was about 3 inches tick and occurred on top of ganister but below 6 or 7 feet from the surface it became hard and unfit for use at the paint works. It passed downwards into a poor quality of coal.

121. Ruabon

Cefn Level. Denbigh 35 S.W.

A possible source of supply of ochre is the Cefn Level, draining coal working from which 30,000 gallons an hour of ochreous water run into the R. Dee. If settling tanks were installed here a large proportion of the ochre could be recovered. The mouth of the level is about 2 miles south-west of Ruabon Station.

124. Cheadle

Reference: Dewey 1920, p.82.

Froghall. Stafford 13 S.W.

In the Cheadle Coalfield a bed known as the Froghall Haematite is found at the base of the Coal Measures. It lies either directly on the First Grit of the Millstone Grit or may be separated from it bu as much as 15ft. of shale. The seam has been practically worked out. Certain patches were worked for making red paint.

There are now no mines working ochre or haematite in the district and the last working mine is said to have closed down about 1930. It was situated on the west Consall and Froghall. The entrance to the mine is covered up and overgrown. It is said locally that plenty of ochre remains to be worked and that a considerable amount of haematite remains untouched.

Westwood. Stafford 12 N.E. Reference: Dewey 1920, p. 83.

In the shaffalong Coalfield search has been made for the Froghall Haematite but only indications have been found. A sinking to the bed was put down at Westwood Manr but no development appears to have taken place.

125. Wirksworth

Reference: Green and Strahan 1887.

Ochre has been got from the Rantor Vein and also from the Foxholes, an open chasm in th Sandhole Vein.

Black oxide of manganese (wad) has been obtained at Hopton, from a hollow in the Toadstone, on the Yokecliff Rake.

145. King’s Lynn. Reference: Woodward 1901, p. 5.

Gaywood. Norfolk 33 N.W.

The lower Greensand (Carstone) has yieldedseveral ferruginous or chalybeate springs one of which, formerly of local repute, occurs at Gaywood. Ochre has been worked at this locality and some iron-ore was obtained at one time near Ash Wicken, Norfolk 34 S.W. and Wormegay.

152. Little Wenlock

Shropshire 43 N.W. Referebce: Pocock 1938, p. 126.

Beds of red bole occur between the Little Wenlock Basalr and the overlying Carboniferous Limestone and might be used as a pigment, but the quantity available is probably very limited.

157. Oakham

Burley Pit, Oackham. Rutland, 5 S.W. S.E.

This pit in the Northampton Ironstone is being worked on alarge scale by Mesrs. Dorman Long & Co. Ltd. for iron-ore. The ore is all of a yellow limonitic type and from it a considerable proportion of yellow ochre can be separated. At the pit there is also a large dump of waste composed of th fies derived from the clamps in which the raw ore has been calcined. From this dumped material a large proportion of a red ochre can be separated.

Yellow ochre washed from the raw ore and red ochre washed from the calcined waste have been submitted to several paint manufacturers. Their reports have, in general, been favourable and indicate that a valuable supply of ochre could be developed from the more weathered outcrops of the Northampton Ironstone bed.

Analyses of the washed samples have been supplied by Messrs. Pinchen Joohnson & Co. Ltd. and show:

	Red	Yellow
Moisture	0.5	0.5
Combined Water	11.3	14.0
Silica	28.0	15.0
Alumina	17.9	12.7
Ferric Oxide	39.5	57.5
Calcium Carbonate	2.1	Traces Only
Undetermined	0.7	0.3
	100.0	100.0

Large quantities of unworkable ore from which ochre could be recovered are tipped behind the workings.

A Barrow Pit near Market Overton and at Cottesmore Pits, Cottesmore, much unworkable ore is used to restore the land it is possible that at these pits also ochre could be recovered from rejected material.

161. Norwich

Reference: Woodward 1881.

Eaton. Norfolk 75 N.W

In describing the contents of some of the pipes or sand galls in the chalk at Eaton, Lyell observed that the fine yellow clay at the bottom of some of the pipes has been found to make a good oil paint of a colour between raw sienna and Roman ochre.

170. Clipston

Near Market Harborough. Northampton 23 N.E

Red ochre is said to have been obtained from the Northampton Beds at Clipston.

201. Banbury

Adderbury. Oxford 10 N.W. Reference: Woodward 1893.

In a trial pit in the park at Adderbury, south of Banbury, the followjg beds of the Midle Lias were penetrated:-

	Feet	Inches
Feruginous marlstone	11	0
Shale	3	0
Grey shelly limestone	1	0
Rusty concretionary bed (“ochre”)		6
Shale	12	0
Pale Blue argillaceous limestone with Concentrations and a concretionary bed below	1	0

Near the railway station at King’s Sutton there were (in 1897) works, belonging to the “Anti-oxide and Colour Company”, where pigments were manufactured. Material had been used from Adderbury, nut the ochre from the Middle Lias proved to be too siliceous and the ingredients were obtained from the neighbourhood of Manchester.

223. Forest of Dean

Reference: Silby 1927.

In the ferriferous dolomite-rock of the Carboniferous Limestone which ranks as iron ore in the Forest of Dean ref haematite is much more abundant than brown haematite. The iron-oxide minerals occur as minutely divided disseminations, and the rocks shade into earthy ochres.

Massive or stalactitic haematite with little or no gangue is termed ‘brush’ by the miners. The ‘brush’ ore shows a patchy development of red and yellow earthy ochres, as alternation products. The quantity of ochre is usually trifling, but occasionally it becomes large. Dolomite-rock rendered highly ferriferous by a dissemination of red haematite and brown haematite (chiefly the former) in microscopic grains constitutes a type of ore which shades insensibly, on the one hand into the moderately ferriferous dolomite-rock that is the usual country of the ores, on the other hand into soft ochres.

The ochres, which occur in intimate association with the ores of the Crease Limestone and have furnished valuable colouring materials, are generally distributed in small quantities; but masses which allow of regular winning appear to be restricted in distribution.

Great quantities of ochre were formerly raised at the ST. Annal’s pit on the eastern side of the Forest of Dean, and the High Meadow Mine, on the western side, was at one time essentially for ochre.

Red ochre predominated greatly, but brown, yellow and pruple varieties are also found.

High Meadow Mine (Robin Hood Pit). Gloucester 30 S.E.

On the west side of the Staunton-Coleford Road, three quarters of a mile south-east of Staunton.

The ochre occurs in lenticular and pockety masses in the upper beds of the Crease Limestone and the lowest beds of the Whitehead Limestone. These masses are liable to be broken up by highly irregular streaks and patches of ‘brush ore’, as well as by unreplaced rock. They have originated partly by the direct replacement of the dolomite-rock, partly by the alteration of the iron-ore.

The best grades of marketable ochre are known as ‘colour’ the inferior grades as ‘spurt’. Inferiority may be due either to relative poorness in ferric oxide or to mottled colouring.

The following are analyses of samples, representing the extremes of high grade and low grade, collected at High Meadow Mine:-

Raw ochres from the High Meadow Mine, near Coleford. Analyses (of air-dried samples) By F. F. Miskin, A.I.C

	I	II
Fe₂O₃	6.52	92.29
FeO	absent	absent
MnO	absent	absent
Al₂O₃	1.96	1.39
SiO₂	6.68	1.36
CaO	26.74	1.04
MgO	17.47	0.58
CO₂	40.22	1.46
P	absent	trace
H₂O (hygroscopic)	absent	0.30
H₂O (combined)	0.35	1.44
Total	99.94	99.86
CaCO₃	47.75	1.86
MgCO₃	36.68	1.22

I. Ochreous dolomite-rock. A finley crystalline, platy dolomite. Thin laminae are highly ochreous and bright or dull red in colour. (Lowest grade of ‘spurt’).

II. Vermilion ochre with flecks of yellow, dark red and purple. Earthy, very fine-grained. (High quality ‘colour’).

Specimens fo the ochreous dolomite-rock, Ni. I above, illustrate clearly the formation of ochre by metasomatic replacement. The haematitization has affected some thin laminae of the rock strongly, and it spreading into the thicker layers from the planes of lamination.

The High Meadow Mine was formerly worked mainly for red ochre, both ochre and ore were carted to Coleford Station, 1½ miles. The mine had produced ome 1,600 tons of ochre up to the end of 1925.

Shakemantle Mines. Gloucester 31 S.E. and 39 N.E.

(Shakemantle, Buckshraft and ST Annal’s)

A considerable but unknown quantity of red ochre (‘colour’) has been won, mainly from St. Annal’s Gale since 1841.

St. Annal’s Pit is situated on the crest of Littledean Hill, on the north-eastern outskirts of Cinderford. It is connected underground with Buckshraft and Shakemantle Pits. And all but the highest level (and possibly that too) are beneath water level. The re-opening of these pits has been mooted several times. It is a practical proposition if there is sufficient ore to warrant the expense of de-watering. Ochre is found in pockets etc. associated with the ore and is, or has been, worked more or less as a by-product.

Old Ham Pit. Gloucester 38 N.E.

This pit was worked principally for ‘colour’ the winning of ore being incidental. Exploration of colour ‘leads’ was in progress in 1927 and ochre was being won for mixing with ochreous clay from a surface deposit in Oakwood Valley.

Lambsquay. Gloucester 38 N.E.

This is a small outcrop gale, west of Milkwall. A bed of ochre was located in Crease Limestone in ground left by old workings.

Noxon Park. Gloucester 39 S.W.

AN old level at the north-west corner of Noxon Park, 100 yds. South-west of the China Engine Pit, was re-opened in 1922; some ore and ochre was won from the Crease Limestone.

Bream. Gloucester 39 S.W.

According to Dr F. M. Trotter there is a deposit of highly ochreous clay near Bream that may be an economic proposition for ‘colour’. It would need analysis to settle the point. The clay occurs as alluvium at the bottom of a steep-sided side-valley on the south-east side of Horwellhill Inclosuree, running down to Oakwood Bottom. An exposure, showing 5ft. of brown ochreous clay, towards the northern end of the strip, indicates the type of material and possibly the whole of the narrow strip of alluvium may be composed of this clay.

237. Oxford District

Shotover Hill near Oxford. Oxfordshire 40 N.W. Reference: Pocock 1926

R. Plot, in 1677, referred to the ochre of Shotover as “being accounted the best in its kind in the world, of a yellow colour and very weighty, much used by Painters simply itself, and as often mix’d with the rest if their colours”.

On Shotover Hill the ironsands, of lower Cretaceous age, were formerly dug on an extensive scale for the ochre, but the industry has long since died out, and the old pits are now either obliterated or greatly obscured. The largest workings seem to have been on the site of the present “allotment gradens”, ½ mile north of Horsepath, and in the park-land north-west of these gardens 100 yds. North of the old coachroad. In the latter locality there is still a partly exposed section showing several feet of yellow sand with intercalated ironstone and traces of clayey beds below. The best exposures available in 1926 were small pits at the western end of the hill south of Wheatley, besides some, more or less obscure, road-cuttings.

Contbeare gives the following section of the ‘Ochre Pits, Shotover Hill’, probably those north of Horsepath.

	Feet
Beds of highly ferruginous grit forming the summit of the hill	6
Grey sand	3
Ferruginous concretions	1
Yellow sand	6
Cream coloured loam	4
Ochre	½

Beneath this is a second bed of ochre separated by a thin bed of clay, then succeeds an interval of nearly 40 feet occupied by various alternations of ferruginous and sometimes cherty and argillaceous loams of a deep cream colour.

In an old pit 200 yds. E.S.E of the windmill at Wheatley, ochre and iron-ore were dug. Prestwich described this pit as being about 12 ft. in depth, consisting of beds of rubbly iron-sandston, impure limonite and yellow ochre.

249 and 262 Glamorganshire

Reference: Sibly 1927

Earthy Ochres, both red and yellow, are generally distributed in very small quantities throughout the haematite ores that are found in the Carboniferous Limestone of Glamorganshire. They have evidently originated as alteration products. Dr. Watson in 1859 recorded the occurrence of yellow ochre in abundance near the crop in the Mwyndy Mine. The Grth, Mwyndy and Trecastle mines produced ochre in small quantities.

Llanharry. Glamorgan 41 N.E.

Red and yellow ochres are here developed in small quantity throughout the ore, evidently as alternation products. Red oxide is produced by the Glamorgan Haematite Iron Ore Co. from Llanharry Mine.

Garth. Glamorgan 36 S.E.

The Garth Mine was abandoned in 1884. Home Office statistics record only an output of some 116,000 tons of ore (iron) during the last eleven years of working, and 176 tons of ochre during the last three years.

The mine is situated one mile north-east of Pentyrch, on the south side of the road to Taffs Well, and one an a quarter miles by road from Taffs Well station on the Taff Vale Railway.

According to F. G. Evans, large cavities in the mine often contained water when tapped, and their floors were sometimes covered with iron-ore and ochre.

264. Winford

Broadfield Down area. Somderset 11 S.E.

Heath Hill 1 mile S. of Winford. References: Buckland and Conybeare 1824, Cantrill and others 1919.

Along the southern foot of the hill the New Red abuts against the Millstone Grit which rests on Carboniferous Limestone. On the further side of a valley extending to the west are the ruddle-pits, for which this district is famous. The highly ferruginous red ochre is very abundant and seems to occur in one of the lowest beds of the New Red Sandstone. It is known as reddle or ruddle.

The position of the Ruddle Pits at Heath Hill; is shown on Weaver’s Mapr (1824).

According to H. B. Woodward (1876) the red ochre is of a clayey nature and occurs in the Dolomitic Conglomerate. It varies in thickness, in places 5 or 6 feet. Pits weer sunk 18 yards in depth. It was used for marking and dressing sheep and as pigment.

In 1917 the deposit was being worked by Winford Iron Ore and Redding Co. Ltd. solely for the red and yellow iron oxides (redding, reddle or ruddle) for use as pigments. The red oxide is accompanied by small masses of hard siliceous haematite of purplish red colour. These re throun aside and collected into heaps. The quantity of this haematite is small. Prof. S. H. Reynolds (1921) records that the principal ironstone and ochre quarry work is opened in Millstone Grit overlain by Triassic beds, which ar ebest seen in the south-western part of the quarry. Here they consist of about three feet of highly ferruginous clay passing up into surface soil, and resting on some four feet of strata, consisting in part of coarse breccia (Dolomitic Conglomerate), in part of fine calcareous and ferruginous beds, yellow when fresh but weathering red. From these Triassic beds yellow ochre is obtained. They rest on the Millstone Grit.

Numerous other workings for ochre, some in use, some abandoned, occur to the north and east of the one described.

Congresbury. Somerset 10 S.E.

There are fissures in the Carboniferous Limestone at Congesbury which contain ochre.

265. Wick

Gloucester 73 S.W. Reference: Reynolds 1921.

The Golden Valley Ochre Works raw materials from ochre diggings in the fields to the north of the hamlet of Wick Rocks. Both red and yellow ochre are quarried, the material being sometimes obtained from surface workings, sometimes by driving small tunnels. One of the shallow pits shows indications of the Rhaetic beds on the top of the Keuper.

At the crossroads towards Doyton is a quarry in ochreous Keuper. The ochre is obtained by tunnelling.

277. Ilfracombe

Devon 5 N.E. Reference: Cantrill and Sherlock 1919.

At Combe Martin, on the coast of the Bristol Channel and 4 miles east of Ilfracombe, iron-ores have been worked in the Devonian Slates. The ironstone raised was brown haematite and siliceous spathic ore.

A Mine on the same lode at Challacombe raised brown haematite and similar ore was produced at Girt Down.

Umber is said to have been worked in the parish of Combe Martin (De La Beche, 1839).

278. Minehead

Somerset 34 N.W. S.E. Reference Cantrill and Sherlock 1919.

Red Haematite has been got a few small mines near Minehead. It was raised many years ago from the Triassic rocks of Porlock, Luccombe (Luckham) and Wootton Courtney, S.E. of Porlock. It occurs as a concentration in the beds if red ferruginous sandstine and conglomerate. The openworks were situated both west and east of Luccombe, and at Brockwell (sheet 294).

279. Hutton

Somerset 17 N.W. Reference: Buckland and Conybeare 1824.

At Huton Hill a cavernous fissure in the Carboniferous Limestone contained ochre, ochreous clay, fragments of Limestone and bones, and pits were at one time opended immediately above the south-east angle of Hutton Wood. On a map by Thomas Weaver published in the Transactions of the Geological Society 1824 the position of these pits is marked in the noth side of Bleydon Hill.

H.B. Woodward (8176) says that the cavern with bones was discovered by workmen digging for ochre.

280. Emborough

Somerset 28 S.E. Reference: Renolds 1921.

The Fuller’s Earth and Ochre Works, long since abandoned, formerly showed a very interesting section of Rhaetic and Keuper beds,

Large pockets of both red and yellow ochre occur in the dolomitic Conglomerate according to Morgan and Reynolds, 1899.

East Harptree. Somerset 19 S.W. Reference: Buckland and Conybeare 1824.

North of the Castle of Comfort the Carboniferous Limestone is covered by shelly chert of Lower Liassic age resting on ochreous sand. This platform is about 2 miles long and one mile broad, extending northwards towards East Harptree. The whole surface is scarred with deep conical and often very extensive hollows, probably ancient ochre-pits; the largest are on the east of the road.

Horizontal strate of dolomitic conglomerate (Trias) lie, in places, beneath the ochreous sand and chert.

H.B. Woodward (1876) remarks that the summit of the platform is covered with blocks of the chert, with which appears also in numerous excavations forming a thick horizontal bed, reposing on ochreous sand. This sand was worked for ochre to the west of the Harptree road. The chert beds are separated by thin clayey beds, some extending to one, two or three feet in thickness, which are charged with yellow ochre and were worked for pigment. The same authority (1893) stated that the largest put is east of the Harptree road, about half way between East Harptree and the Castle of Comfort. It is about 60 feet in diameter at the mouth, is funnel-shaped, and about 20 to 30 feet in depth. It is evidently a natural 2pot2 or wallet-hole.

The section consists almost entirely of massive bedded chert occurring in layers of from one to three feet in thickness, standing out sharply, but sometimes weathering sandy at the exterior, and separated by thin clayey beds an inch or two in thickness.

Most of the ochre appears to have been obtained from clayey beds at or near the base of the chert as well as from clayey seams between the beds of stone and from the Dolomitic Conglomerate.

Banwell. Somerset 17 N.W., N.E.

Ochre has been dug in fissures of the Carboniferous Limestone at Banwell. A recent account of Banwell Cave is given by Wadsworth and Sharpe, 1938.

Ashwick. Somerset 29 S.W.

A hard, heavy, pale yellow ochre is said to occur at this locality, apparently in the Triassic Dolomitic Conglomerate.

Ebbor Rocks. Somerset 27 S.E.

Yellow ochre and reddle are found in the Triassic Dolomitic Conglmoerate near Ebbor Rocks, two miles north-west of wells.

285. Woking

Knaphill. Surrey 16 S.E.

A sand rich in glauconite is being worked in the Bracklesham Beds at Knaphill Brickworks near Woking. The glauconite can be conventrated by screening and expirement shows that it then yields, on grinding, a pleasing green pigment. No tests of its permanence or other properties have been made (see Introduction).

292 - 293. Bideford

Devon 19 N.W, N.E. References: De La Beche 1839, H.B. Woodward 1887.

Beds of Culm stretch across country from Barnstaple Bay and Bideford towards Chittlehampton, west of South Molton and have been worked at different periods. A soft variety of the anthracite or Culm, used as mineral black, is raised near Bideford by Bideford Black Pigments Ltd. from a bed known as the Chapel Park Paint Seam.

The anthracite occurs in a few beds of very variable thickness between Greenacliff on the coast west from Bideford and Hawkridge Wood on the right bank of the R. Taw, near Chittlehampton a distance of about twelve miles and a half. The beds are generally accompanied by black shalves.

The Greenacliff anthracite is continued in an east direction through the town of Bideford where the beds vary from 6 inches to 14 feet and were formerly worked, they are more fully developed about a mile inland on the right bank of the Torridge.

Near Alverdiscot a bed of anthracite has been traced for about a mile from near the church to Woodland Farms.

At Hiscott (Eastacot) in the parish of Tawstock there are two veins 9 feet in thickness. They were first worked about the latter half of the 18^th century and although the anthracite was of excellent quality the mines were closed about the year 1800 on account of water difficulties.

At Umberleigh, Hawridge Wood, on the Taw, the anthracite beds terminate to the eastward.

293. North Molton and Barnstaple.

Reference: Cantrill and others 1919.

In the neighbourhoods of North Molton, between Dulverton and Barnstaple, several mines have raised ironstone, apparently red and brown haematites, with some spathic ore.

The ore occurs in a copper-bearing belt of veinlets crossing the valley of the Mole about two miles north of North Molton.

Bampfydle Mine. Devon 15 N.W.

In 1870 this mine was 110 fathoms deep and produced 7,187 tons of iron ore in 1873-74. In 1880 some 1,309 tons of brown haematite were sold.

Florence Mine. Devon 15 N.W.

Yielded spathic ore and haematite

Stowford Mine. Devon 15 N.W.

Produced red and brown haematite.

Barnstaple District.

Mines ar Shirwell and Bratton Fleming, 5 miles north-east of Barnstaple, produced brown haematite and Spraycombe Mine yielded similar ore.

East Down

According to De La Beche (1839) a large quantity of ochre is said to have been found and manufactured in the parish of East Down.

294. Brendon Hills and Eisen Hills.

Somerset 46 S.W., S.E.; 47 S.W.; 58 N.W., N.E.; 59 N.W.

References: Cantrill and others 1919

The mines of the Brendon Hills produced, in depth, chalybite (feC0³) contains a large proportion of manganese, but near the surface it has been converted into manganiferous limonite and haematite. Intermediate varieties were known as ‘brown ore’, ‘black ore’ and ‘potty ore’; these were dark brown and generally more or less cellular.

Some of the surface material might be of use for colour and the chalybite of the unoxidzed portion of the vein if calcined would yield a red pigment. No ore has been raised in this district for many years.

The mines at Eisen Hill yielded excellent brown ore of the variety called pitchy ore, with some crystalline limonite, &c. This ore might be considered as possible source of ochre or umber.

295. Quantock Hills.

Reference: Ussher 1908.

Between Stogumber and Monksilver, Somerset 48 S.W., the soil is deepl peroxidated but no lodes have been detected even where one might expect the pro-longation of the Brendon Hill (294) lodes between Tolland (Somerset 59 N.W.) and Stogumber.

The same series of rocks probably occupies the area between Thurloxton (Somerset 61 S.W.) and Cothelstone ( Soemrset 60 S.W.) in the southern part of the Quantock Range.

On the south of Merridge (Somerset 60 N.E.) on the Quantocks, an unprofitable attempt to work iron-ore was at one time made. On main (or Mawn) down on the west of Wiveliscombe (Somerset 69 N.W.) haematite has been detected.

312. Yeovil.

Reference: Woodward 1893

Here and there as at Sock, (in the sands below the Middle Lias Marlstone), we find laminated micaceous and sandy shales, with calcareous bands and nodules of ochre and “race”.

335, 336. Padstow and Camelford.

Treylyn Mine, St. Minver. Cornwall 19 S.W. Rference: MacAlister 1910.

Two lodes have been worked at this mine. A north and south lead lode hading west and a lode of umber running a little east of north.

337. Tavistock

Halwell Ochre Works. Cornwall 22 N.E. Three quarters of a mile east by north of Coad’s Green.

The following motes were made by Mr H. G. Dines in 1940. The pit, about a quarter of an acre in extent and from 10 to 12 ft. deep is in decomposed pyroclastic rocks (apparently of Devonian age). The decomposition is not complete, some hard cores retaining their original structure to some extent. The osft material where free from grit is used for pigment and varies in colour from red to orange-brown, bright yellow and pale buff-yellow.

The deposit is said to be workable down to 30 or 40 ft. from the surface, below which level it becomes to clayey. The pit face shows the deposit to be traversed by a few ramifying quartz veins uo tp 3 inches thick. There are also irregular bands of secondary pan due to cementation by limonite.

The working was commenced about 20 years ago, when an embankment and cutting were constructed to carry a light railway from the pit to a storage shed near the road.

Twice since then work has been restarted but carried on only for a short time. The present work was begun in 1940 by Messrs. Sherman & Co. and about 1,000 tons of ochre are said to have been sold. Early in August 1940 the property was acquired by the Golden Valley Ochre and Oxide Co.

The material is hand sorted in the pit, only the good quality ochre being sent away. This represents about 25 per cent of the whole rock, whereas washing and resettling would probably increase the recovery to perhaps 60 or 70 per cent.

Trecarrell. Cornwall 22 N.E. Reference: MacAlister 1911.

A quarry in fine-grained non-vesicular rock (lava), which may be of Carboniferous age, is situated in a small wood 500 yds. North of Trecarrell Bridge, 4½ miles south by west of Launceston. Where the lava has been greatly decomposed it is reduced to a soft ochreous matieral which has been worked as a source of paint.

Lezant. Cornwall 23 N.W.

A deposit of ochre at Higher Larrick, Lezant, is being worked by Tmar Valley Minerals Ltd. and between High Larrick and Trecarrell ochre has been got at several places on the site of Old Larrick Mine. The ochre was formed by the decomposition of lava of Devonian or Carboniferous age.

Chillaton Barton. Devon 97 N.W.

Ochre of good quality is being worked by the Tamar Valley Company on a property known as Chillaton Barton, about half a mile south of Chillaton Village. The ochre is associated with manganese and is adjacent to the Hogstor-Chillaton Manganese workings.

Whitstone Mine. Devon 97 N.E. Reference: MacAlister 1911. Near Bowden Down, Brentor

Deposits of ochre were formerly worked in this mine along with manganese, and 154 tons of ochre were produced in 1899.

338. Dartmoor.

Reference: MacAlister 1912.

Oxides of iron occurring in veins on the eastern broders of Dartmoor have been produced in considerable quantities and comprise magnetite, specular iron ore, and brown haematite (ochre and umber). Specular iron ore has been produced in small quantities by Birch Tor and Vitifer Mine, while brown haematite for use as iron ore in the form of ochre and umber has been raised from the Devon and Cornwall United Mine, Smallacombe, South Devon Mine and other places.

The magnetite of Haytor has been converted, near the surface, into ochre by the action of atmospheric agencies and has been worked for that substance.

Ashburton. Devon 108 S.E. Reference: Frochville 1887.

Several patches of limestone of Devonian age associated with clay slates occur near Ashburton. One of these extends two or three miles north-east of the town.

The beds dip to the south-east. The upper beds are massive grey rock quarried for lime and building. The lower beds, 20 to 30ft. thick, are dolomotic and decompose into umber which has been worked for may years.

The dolomitic is a separated by thin shales from igneous rock.

The raw material is a gritty earth from which the umber is separated by crushing and washing. It is used in the manufacture of silicate oxide paint, for colouring coarse cloth and brown paper.

The following analyses are of the dolomite and of the umber as mined.

Dolomite		Umber
Water (Lost at 100º)	0.8	Water(Lost at 100º)	65.0
CaCO₃	46.7	Combined Water	4.8
MgCO₃	41.0	Lime	0.6
Silica	3.3	Silica	12.3
FeCO₃	2.6	Sesquioxide	6.3
MnCO₃	2.5	Binoxide of manganese	10.0
Loss	3.1	Loss and undetermined	1.0

Haytor Iron Ore Mines, Ilsington. Devon 100 S.E. Reference: Cantrill and others 1919.

The 'lode' consists of four district bands lying among altered shales and sandstones (Culm Measures).

The ore consists of remarkably pure magnetite, often in octahedral crystals, associated with a mass if actinolite or fibrous hornblende. Some spathic iron-ore occurs.

Smallacombe Iron Mine, Ilsington. Devon 100 S.E. Reference: Cantrill and others 1919.

Limonite and magnetite are present. The limonite contains 43 per cent of iron and 4 of manganese.

Umber has been worked in the upper part of the magnetite-lode where decomposed, and contains at a few fathoms from the surface large quantities of garnet rock and hornblende.

Moor Wood Mines. Devon 90 S.E. Pepperdon Estate, Moreton Hampstead.

At this locality, near Wray Barton, good quality micaceous iron-ore is being mined, for use in the manufacture of special paints for electric welding rods, and as a lubricant, by Messrs. Nicol and New Ltd.

339. Newton Abbot

References: Ussher and others 1913, Cantrill and others 1919.

Torbryan. Devon 115.N.W. Near Broadway, east of Torbryan, Devonian dolomitic limestones, apparently containing umber and resembling the beds worked for umber near Ashburton (338), are exposed.

Goodstone. Devon 108 S.E. In the umber pits at Goodstone, 4 miles west of Newton Abbot, the dolomitic limestone has been worked under a thick soil consisting of about 8 feet of yellow loamy clay, probably decomposed igneous material, under 5 feet of clay, with purple igneous and slate fragments. Through this the rock project in large fretted masses in places.

Lustleigh and Hennock area

Devon 101 N.W. Reference: Cantrill and other 1919.

A considerable amount of specular iron ore (‘shining ore’) and small amounts of brown haematite (ochre and umber), spathic iron ore, etc. have been obtained in the past. The micaceous or shining ore is a well-known product of the region and is particularly abundant in the veins in the granite of this area. The veins have a general bearing ranging east 20º north to east and west, and a width ranging from 1 to 12 feet.

Shining ore from Hawkmoor, Plumley and Shaptor mines has been used for paint making.

AT Kelly Mine, Ferrubron Maunfacturing Co. Ltd, the ore is a variety of specular haematite, occurring in very fine scales and described as micaceous iron-ore. Considerable quantities have been raised under the name of ‘shining ore’ and exported.

At Great Rock Mine the country-rock is mineralised granite and the ore consists of micaceous haematite identical in character with that at Kelly Mine and is worked by the same Company.

Wolborough, Chudleigh, &c. Reference: MacAlister 1913.

At one time a considerable quantity of brown haematite was obtained at Wolborough on the southern outskirts of Newton Abbot (Devon 101 S.E.) and also at Ugbrooke Park, near Chudleigh (Devon 101 S.E.). Ochre ia said to have been manufactured at Aller south of Newton Abbot (Devon 115 N.E.) and it occurs at irregular masses in limestone near Bishopsteighton (Devon 110 N.W.).

346. Newquay.

Reference: MacAlister 1906.

A little red ochre and umber have been raised from mines in this area. The Duchy and Peru Mine (Cornwall 48 N.E.), for example, produced 180 tons of ochre and umber between 1848 and 1903. The shafts are situated at Rejerrah. The lode is the Great Perran Lode of which an interesting account is given by Dewey (1919, pp. 61 to 63).

347. Bodmin and St Austell.

Reference: Dewey 919.

Between 1886 and 1902 this district produced 1,280 tons of ochre and umber. At the Toldish and Indian Queen’s Mine, near Ruthvoes (Cornwall 40 N.E.) the main lode, known as the Caverigan Lode, has been worked by opencast. The bearing in N. 33ºW. It can be traced north-westwards through the farm of Treliver by the red colour of the soil and by old trials here and there.

In it north-westerly extension it has a bearing N. 50º W. The material mainly red haematite, but brown haematite also occurs, and the mine was worked largely for ochre and umber. It is said that the lode consisted of oxide of iron and quartz.

The Indian Queen Mine was worked by the Indian Queen and Colour Company Ltd. at whose works paint was manufactured from the haematite.

348. Plymouth and Liskeard.

Reference: Ussher 1907.

The purple and green Upper Devonian slates of Wivelscombe Quarry, after being ground up an dlixed with other materials, produce a deep red pigment.

349. Ivybridge.

Reference: Ussher 1912.

Umber is said to have been obtained at Dean and it has been worked in the Buckfastleigh area, where its occurrence is similar to that in the Ashburton limestone (338). There are also umber works (disused) in open pits it calcflintas on either side of the road by Torrs Wood (east of the Plymouth Asylum), Cornwall 119 S.E.

350. Brixham.

Reference: Dewey 1919.

In the Brixham district red and brown haematite have been worked at a number of small mines, especially near Sharkham Point. Most of the ore is sold for paint making. The ores form irregular bodies filling pockets and fissures in the Devonian limestone. In 1917 4,000 tons were produced.

The outcrop of “Permian” marke on the one0inch map, between Brixham and Fishcombe Point, is now represented by a deep disused hollow from which material is said to have been extracted for the old iron ore and paint works nearby.

The Tor Bay Paint Company obtained raw material from a surface excavation on the southern border of the Devonin limestone plain of east Brixham, in the form of an ochreous clay which fills a large pocket in the limestone; the dimensions of the pocket have not yet been proved, but many thousands of tons of clay have been removed.

351. See 358.

352. Falmouth and Truro.

Reference: Hill and MacAlister 1906.

Bissoe

There are ochre works in the valley at Bisseo near Carnon, south-west of Truro, which at the time of the survey in 1902 were said to have been in continuous operation for over 40 years. The oxide of iron, carried in suspension, in the waters, draining vein workings, that discharge from the main adit into the Carnon Stream, is caught in small pools, after which by fires, and in summer by the sun. The works are small, and there is no continuous market for the product.

Killiow. 2 miles south-west of Truro.

By preparing a clay, naturally coloured by iron, from a decomposed elvan, on the west of Killiow, a very excellent yellow ochre is obtained and considerable quantities of it are sent from thence (de La Beche 1839).

The total yield of ochre and umber, in the Truro District, from 1848 to 1905 was about 900 tons.

353. Mevagissey

Great Perhaver Point approached by a rough track to the ruined house of the abandoned ochre mine.

The ochre mine is at the top of the cliff. The workings are now overgrown. An iron platform was once used for shipping the ochre. The mine, which was a failure, seems to have been worked in a band of weathered lava separated by slate from the main mass, but its relations are difficult to make out.

The small bay between Percunning Cove and Black Rock is occupied by black and striped slates, like those near the ochre mine. In the rocks immediately east of Black Rock an adit has been driven into black slates with lenticles of quartzite. The water that issues from it deposits much limonite and also tufa. The adit appears to have been driven along the spring in search of the iron ochre.

351 and 358. Land’s End

Ochre has been obtained in St. Ives ( Mine ?).

The output in the Land’s End district since 2854 has been

		tons
Binner Downs	Brown haematite	100
Wheal Castle	Brown haematite	75
Trebarvah	Brown haematite	1730

At Hawkes Point a ton of ochre was obtained.

Ochres, umbers and other natural earth pigments of England and Wales