Metalliferous mineralization, Southwest Scotland - Revision history

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	3 Mineralisation type: A— associated with ultrabasic rocks; B — associated with Ordovician or Silurian sedimentary rocks; C — associated with diorite and granodiorite; D — haematite vein; E — lead-zinc vein; F — copper, antimony and/or arsenic veins; G — baryte vein; H — uranium vein.		3 Mineralisation type: A— associated with ultrabasic rocks; B — associated with Ordovician or Silurian sedimentary rocks; C — associated with diorite and granodiorite; D — haematite vein; E — lead-zinc vein; F — copper, antimony and/or arsenic veins; G — baryte vein; H — uranium vein.

			[[Category:Mineral resources]]

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Metalliferous mineralization

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	By M J Gallagher. From: Stone, P (editor). 1996. Geology in south-west Scotland: an excursion guide. Keyworth, Nottingham: British Geological Survey.		By M J Gallagher. From: Stone, P (editor). 1996. Geology in south-west Scotland: an excursion guide. Keyworth, Nottingham: British Geological Survey.
	== Metalliferous mineralization ==		== Metalliferous mineralization of south-west Scotland==

	=== Introduction ===		=== Introduction ===

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Appendix 1 Metalliferous mineralization

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	== ~~Appendix 1~~ Metalliferous mineralization ==		By M J Gallagher. From: Stone, P (editor). 1996. Geology in south-west Scotland: an excursion guide. Keyworth, Nottingham: British Geological Survey.
	~~'''By M J Gallagher'''~~		== Metalliferous mineralization ==

	=== Introduction ===		=== Introduction ===

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	=== Introduction ===		=== Introduction ===
	Most of the mineral locations in south-west Scotland are veins, many of which were trialled or mined for lead, copper and zinc in the 18th and 19th centuries, with limited work continuing in places until about 1920 (Wilson, 1921). Production of haryte from Barlocco probably continued until 1954.		Most of the mineral locations in south-west Scotland are veins, many of which were trialled or mined for lead, copper and zinc in the 18th and 19th centuries, with limited work continuing in places until about 1920 (Wilson, 1921). Production of haryte from Barlocco probably continued until 1954.
			[[File:SWScotlandMetalliferousMineralization.jpg\|500px\|thumbnail\|Location of significant metalliferous mineralisation in south-west Scotland. Full details are listed in the table below.]]

	Subsequently, uranium veins and both disseminated and vein occurrences of minerals of arsenic, molybdenum, lead, copper and zinc were discovered using modern techniques, but none has proved economic. Minor quantities of gold have also been discovered recently at several localities.		Subsequently, uranium veins and both disseminated and vein occurrences of minerals of arsenic, molybdenum, lead, copper and zinc were discovered using modern techniques, but none has proved economic. Minor quantities of gold have also been discovered recently at several localities.


	The known mineral veins of south-west Scotland are concentrated at the southern and western margins of the granitic complexes of Cairnsmore of Fleet in the west, and Criffell in the east. The composition of the veins changes in a general way from dominantly lead-zinc in the west to copper, barium and uranium in the east. The veins are highly variable in trend (Table 5), cutting sedimentary rocks of Ordovician to Lower Carboniferous age and intrusions of diorite, granodiorite and granite dated isotopically at late Silurian to early Devonian (Stephens and Halliday, 1984; Stephens et al., 1985). The lead-zinc vein at Blackcraig may postdate a dyke of Permo-Carboniferous type (Gallagher, 1964) and pitchblende from one of the Dalbeattie veins has yielded a Mesozoic age (Miller and Taylor, 1966).		The known mineral veins of south-west Scotland are concentrated at the southern and western margins of the granitic complexes of Cairnsmore of Fleet in the west, and Criffell in the east. The composition of the veins changes in a general way from dominantly lead-zinc in the west to copper, barium and uranium in the east. The veins are highly variable in trend (Table 5), cutting sedimentary rocks of Ordovician to Lower Carboniferous age and intrusions of diorite, granodiorite and granite dated isotopically at late Silurian to early Devonian (Stephens and Halliday, 1984; Stephens et al., 1985). The lead-zinc vein at Blackcraig may postdate a dyke of Permo-Carboniferous type (Gallagher, 1964) and pitchblende from one of the Dalbeattie veins has yielded a Mesozoic age (Miller and Taylor, 1966).


	Eight types of mineralisation (A–H) are described in this account, with reference to 29 of the more significant mineral locations in the region (located on Figure 67). Much further information can be found in the geochemical atlas ''Regional geochemistry of southern Scotland and part of northern England ''(British Geological Survey, 1993c) which contains coloured distribution maps for many elements.		Eight types of mineralisation (A–H) are described in this account, with reference to 29 of the more significant mineral locations in the region (located on Figure 67). Much further information can be found in the geochemical atlas ''Regional geochemistry of southern Scotland and part of northern England ''(British Geological Survey, 1993c) which contains coloured distribution maps for many elements.

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	=== F Copper, antimony and arsenic veins ===		=== F Copper, antimony and arsenic veins ===
	[[File:P001528.jpg\|~~300px~~\|thumbnail\|Pibble Mine engine house, 5 km. east-north-east of Creetown, on the north-west slope of Pibble Hill, Kirkudbrightshire. A former lead-zinc mine that worked a four-feet wide vein trending 20 degrees north of west and hading to the west at from 75 to 80 degrees. The vein comprised broken country rock with quartz and barytes and carrying a little galena (lead ore), zinc-blende and chalcopyrite and other minor minerals. The hade is the angle at which the vein dips. P001528.]]		[[File:P001528.jpg\|400px\|thumbnail\|Pibble Mine engine house, 5 km. east-north-east of Creetown, on the north-west slope of Pibble Hill, Kirkudbrightshire. A former lead-zinc mine that worked a four-feet wide vein trending 20 degrees north of west and hading to the west at from 75 to 80 degrees. The vein comprised broken country rock with quartz and barytes and carrying a little galena (lead ore), zinc-blende and chalcopyrite and other minor minerals. The hade is the angle at which the vein dips. P001528.]]
	Foster-Smith (1967) refers to Pibble Mine (18) as the dominant 19th century copper producer in south-west Scotland, although no production figures are given by Wilson (1921). The vein, about 1 m thick, cuts Silurian greywackes interbedded with black shales some 3 km south of the southern contact of the Cairnsmore of Fleet granitic pluton. It contains lenses of galena, sphalerite and chalcopyrite and, unusually for the veins of south-west Scotland, a variety of secondary minerals. These include linarite, pyromorphite, hemimorphite and malachite, all recorded from the upper levels of the mine. A variety of ruined mine buildings and spoil dumps remain at the site. Also to the south of the Cairnsmore of Fleet pluton, chalcopyrite-bearing veins have been trialled at Drumruck (16), Dromore (17) and Kings's Laggan (19).		Foster-Smith (1967) refers to Pibble Mine (18) as the dominant 19th century copper producer in south-west Scotland, although no production figures are given by Wilson (1921). The vein, about 1 m thick, cuts Silurian greywackes interbedded with black shales some 3 km south of the southern contact of the Cairnsmore of Fleet granitic pluton. It contains lenses of galena, sphalerite and chalcopyrite and, unusually for the veins of south-west Scotland, a variety of secondary minerals. These include linarite, pyromorphite, hemimorphite and malachite, all recorded from the upper levels of the mine. A variety of ruined mine buildings and spoil dumps remain at the site. Also to the south of the Cairnsmore of Fleet pluton, chalcopyrite-bearing veins have been trialled at Drumruck (16), Dromore (17) and Kings's Laggan (19).

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F Copper, antimony and arsenic veins

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	=== F Copper, antimony and arsenic veins ===		=== F Copper, antimony and arsenic veins ===
	[[File:P001528.jpg\|thumbnail\|Pibble Mine engine house, 5 km. east-north-east of Creetown, on the north-west slope of Pibble Hill, Kirkudbrightshire. A former lead-zinc mine that worked a four-feet wide vein trending 20 degrees north of west and hading to the west at from 75 to 80 degrees. The vein comprised broken country rock with quartz and barytes and carrying a little galena (lead ore), zinc-blende and chalcopyrite and other minor minerals. The hade is the angle at which the vein dips. P001528.]]		[[File:P001528.jpg\|300px\|thumbnail\|Pibble Mine engine house, 5 km. east-north-east of Creetown, on the north-west slope of Pibble Hill, Kirkudbrightshire. A former lead-zinc mine that worked a four-feet wide vein trending 20 degrees north of west and hading to the west at from 75 to 80 degrees. The vein comprised broken country rock with quartz and barytes and carrying a little galena (lead ore), zinc-blende and chalcopyrite and other minor minerals. The hade is the angle at which the vein dips. P001528.]]
	Foster-Smith (1967) refers to Pibble Mine (18) as the dominant 19th century copper producer in south-west Scotland, although no production figures are given by Wilson (1921). The vein, about 1 m thick, cuts Silurian greywackes interbedded with black shales some 3 km south of the southern contact of the Cairnsmore of Fleet granitic pluton. It contains lenses of galena, sphalerite and chalcopyrite and, unusually for the veins of south-west Scotland, a variety of secondary minerals. These include linarite, pyromorphite, hemimorphite and malachite, all recorded from the upper levels of the mine. A variety of ruined mine buildings and spoil dumps remain at the site. Also to the south of the Cairnsmore of Fleet pluton, chalcopyrite-bearing veins have been trialled at Drumruck (16), Dromore (17) and Kings's Laggan (19).		Foster-Smith (1967) refers to Pibble Mine (18) as the dominant 19th century copper producer in south-west Scotland, although no production figures are given by Wilson (1921). The vein, about 1 m thick, cuts Silurian greywackes interbedded with black shales some 3 km south of the southern contact of the Cairnsmore of Fleet granitic pluton. It contains lenses of galena, sphalerite and chalcopyrite and, unusually for the veins of south-west Scotland, a variety of secondary minerals. These include linarite, pyromorphite, hemimorphite and malachite, all recorded from the upper levels of the mine. A variety of ruined mine buildings and spoil dumps remain at the site. Also to the south of the Cairnsmore of Fleet pluton, chalcopyrite-bearing veins have been trialled at Drumruck (16), Dromore (17) and Kings's Laggan (19).

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	=== F Copper, antimony and arsenic veins ===		=== F Copper, antimony and arsenic veins ===
			[[File:P001528.jpg\|thumbnail\|Pibble Mine engine house, 5 km. east-north-east of Creetown, on the north-west slope of Pibble Hill, Kirkudbrightshire. A former lead-zinc mine that worked a four-feet wide vein trending 20 degrees north of west and hading to the west at from 75 to 80 degrees. The vein comprised broken country rock with quartz and barytes and carrying a little galena (lead ore), zinc-blende and chalcopyrite and other minor minerals. The hade is the angle at which the vein dips. P001528.]]
	Foster-Smith (1967) refers to Pibble Mine (18) as the dominant 19th century copper producer in south-west Scotland, although no production figures are given by Wilson (1921). The vein, about 1 m thick, cuts Silurian greywackes interbedded with black shales some 3 km south of the southern contact of the Cairnsmore of Fleet granitic pluton. It contains lenses of galena, sphalerite and chalcopyrite and, unusually for the veins of south-west Scotland, a variety of secondary minerals. These include linarite, pyromorphite, hemimorphite and malachite, all recorded from the upper levels of the mine. A variety of ruined mine buildings and spoil dumps remain at the site. Also to the south of the Cairnsmore of Fleet pluton, chalcopyrite-bearing veins have been trialled at Drumruck (16), Dromore (17) and Kings's Laggan (19).		Foster-Smith (1967) refers to Pibble Mine (18) as the dominant 19th century copper producer in south-west Scotland, although no production figures are given by Wilson (1921). The vein, about 1 m thick, cuts Silurian greywackes interbedded with black shales some 3 km south of the southern contact of the Cairnsmore of Fleet granitic pluton. It contains lenses of galena, sphalerite and chalcopyrite and, unusually for the veins of south-west Scotland, a variety of secondary minerals. These include linarite, pyromorphite, hemimorphite and malachite, all recorded from the upper levels of the mine. A variety of ruined mine buildings and spoil dumps remain at the site. Also to the south of the Cairnsmore of Fleet pluton, chalcopyrite-bearing veins have been trialled at Drumruck (16), Dromore (17) and Kings's Laggan (19).

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	=== C Associated with diorite and granodiorite ===		=== C Associated with diorite and granodiorite ===
	Base and precious metal mineralisation is located in or near the margins of several diorite–granodiorite intrusion in south-west Scotland. Three varieties can be recognised.		Base and precious metal mineralisation is located in or near the margins of several diorite–granodiorite intrusion in south-west Scotland. Three varieties can be recognised.
			[[File:P527559.jpg\|400px\|thumbnail\|A specimen of arsenopyrite, an iron arsenic sulphide from Talnotry about six miles south-west of Newton Stewart. British Geological Survey Petrology Collection sample number MC 7339. An old abandoned mine is located on the west side of Palnure Burn 250 yards south-east of Talnotry Cottage. The deposit is said to have been discovered in about 1885 and was first opened up by a small syndicate. It was mined for its pyrrhotite and niccolite ore. Arsenopyrite is a hard, very heavy, fragile mineral with good cleavage and is regarded as the principal ore of arsenic with tin, gold, silver and cobalt as by-products. P527559.]]

	'''i The Talnotry deposit''' (11) is the only instance of a magmatic copper-nickel ore-body in the Southern Uplands. The host rock is a late Caledonian diorite sill in which a basal lens of sulphide, 4 X 20 m in size, contains pyrrhotite, pentlandite, chalcopyrite, nickeline and gersdorffite, plus numerous minor constituents including gold (Stanley et al., 1987).		'''i The Talnotry deposit''' (11) is the only instance of a magmatic copper-nickel ore-body in the Southern Uplands. The host rock is a late Caledonian diorite sill in which a basal lens of sulphide, 4 X 20 m in size, contains pyrrhotite, pentlandite, chalcopyrite, nickeline and gersdorffite, plus numerous minor constituents including gold (Stanley et al., 1987).

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	=== D Haematite veins ===		=== D Haematite veins ===
			[[File:P527659.jpg\|400px\|thumbnail\|Haematite from Auchenleck, Kirkudbrightshire. At Auchenleck, about five miles east of the town of Kirkcudbright a haematite vein occurs in the Dalbeattie granite mass. British Geological Survey Petrology Collection sample number MC 7439. The trend of the vein is west 18 degrees north and it is the most important vein of iron ore in the district. Hay Cunningham's 'Geognostical Account of the Stewartry of Kirkcudbright' (Highland Society's Transactions v. viii, 1843 p. 730) describes the vein as being mined by a horizontal shaft. 'The ore is of red botryoidal haematite and, in drusy cavities fine specimens of this beautiful mineral may be found. The minerals which accompany the iron-ore are ferruginous quartz and sulphate of barytes.' ]]
	Fracture-bound haematite deposits are located at the margins of the Criffell granodiorite pluton (Phillips, 1956) and a weakly radioactive deposit occurs within the granodiorite (see Type H). The Auchenleck vein (25) was the most important economically, consisting of botryoidal haematite, quartz and baryte. The NE margin of the Loch Doon granitic pluton is transected by a haematite breccia vein, 0.5 m to at least 3 m in width, which has been prospected and/or mined over some 3 km of strike length. The occurrence lies about 7 km west of Carsphairn (5) and has yielded around 400 tonnes of haematite (Excursion 7).		Fracture-bound haematite deposits are located at the margins of the Criffell granodiorite pluton (Phillips, 1956) and a weakly radioactive deposit occurs within the granodiorite (see Type H). The Auchenleck vein (25) was the most important economically, consisting of botryoidal haematite, quartz and baryte. The NE margin of the Loch Doon granitic pluton is transected by a haematite breccia vein, 0.5 m to at least 3 m in width, which has been prospected and/or mined over some 3 km of strike length. The occurrence lies about 7 km west of Carsphairn (5) and has yielded around 400 tonnes of haematite (Excursion 7).

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	Base and precious metal mineralisation is located in or near the margins of several diorite–granodiorite intrusion in south-west Scotland. Three varieties can be recognised.		Base and precious metal mineralisation is located in or near the margins of several diorite–granodiorite intrusion in south-west Scotland. Three varieties can be recognised.

	''i The Talnotry deposit'' (11) is the only instance of a magmatic copper-nickel ore-body in the Southern Uplands. The host rock is a late Caledonian diorite sill in which a basal lens of sulphide, 4 X 20 m in size, contains pyrrhotite, pentlandite, chalcopyrite, nickeline and gersdorffite, plus numerous minor constituents including gold (Stanley et al., 1987).		'''i The Talnotry deposit''' (11) is the only instance of a magmatic copper-nickel ore-body in the Southern Uplands. The host rock is a late Caledonian diorite sill in which a basal lens of sulphide, 4 X 20 m in size, contains pyrrhotite, pentlandite, chalcopyrite, nickeline and gersdorffite, plus numerous minor constituents including gold (Stanley et al., 1987).

	'''ii Volcanic porphyry Cu-Mo-Au-Ag mineralisation.''' This is exemplified by disseminations and veinlets of mineral in diorite complexes. The Fore Burn complex (2) is a Lower Devonian igneous assemblage lying immediately north of the Southern Upland Fault. Arsenopyrite, pyrite, chalcopyrite, gold, silver and tetrahedritetennantite occur in quartz-carbonate veins and in small intrusion breccias which are intensely tourmalinised. Gold is also present locally in quartz-arsenopyrite-chalcopyrite veins. Grades varying up to about 50 gm per tonne are reported by Charley et al. (1989). Porphyry-style copper mineralisation is weakly developed in a late Caledonian complex of intersecting porphyrite dykes, gran odiorite intrusions and breccia pipes at Black Stockarton Moor (22) on the western margin of the Criffell granodiorite pluton (Leake and Cooper, 1983). Breccia veins are enriched in As, Sb and gold (maximum 0.06 ppm Au in samples) in association with molybdenite (350 ppm Mo) and with chalcopyrite and bornite (4400 ppm Cu). In one borehole, an average of 0.05 per cent Cu was maintained over 34 m (Leake and Brown, 1979).		'''ii Volcanic porphyry Cu-Mo-Au-Ag mineralisation.''' This is exemplified by disseminations and veinlets of mineral in diorite complexes. The Fore Burn complex (2) is a Lower Devonian igneous assemblage lying immediately north of the Southern Upland Fault. Arsenopyrite, pyrite, chalcopyrite, gold, silver and tetrahedritetennantite occur in quartz-carbonate veins and in small intrusion breccias which are intensely tourmalinised. Gold is also present locally in quartz-arsenopyrite-chalcopyrite veins. Grades varying up to about 50 gm per tonne are reported by Charley et al. (1989). Porphyry-style copper mineralisation is weakly developed in a late Caledonian complex of intersecting porphyrite dykes, gran odiorite intrusions and breccia pipes at Black Stockarton Moor (22) on the western margin of the Criffell granodiorite pluton (Leake and Cooper, 1983). Breccia veins are enriched in As, Sb and gold (maximum 0.06 ppm Au in samples) in association with molybdenite (350 ppm Mo) and with chalcopyrite and bornite (4400 ppm Cu). In one borehole, an average of 0.05 per cent Cu was maintained over 34 m (Leake and Brown, 1979).