MineralsUK Expert | Impartial | Innovative Centre for sustainable mineral development RAW MATERIALS FOR DECARBONISATION www.mineralsUK.com The potential for cobalt in the UK MAY 2020 Introduction Cobalt is a lustrous, silvery-grey metal with many physical and chemical properties that make it useful in a wide variety of chemical and metallurgical applications (Petavratzi et al., 2019). In the UK cobalt is used in high- performance alloys for the aerospace sector and in the cemented carbide, magnet and special steel industries. Cobalt chemicals are used in the manufacture of batteries, glass and ceramics (Petavratzi et al., 2019). The UK imports cobalt in several forms, chiefly as unwrought metal. In 2017 the total apparent consumption of cobalt in the UK amounted to about 1500 tonnes of contained cobalt metal (Bide et al., 2019). Between 1993 and 2017 mine production of cobalt Canada (5%) and Australia (4%). Cobalt produced increased at a compound annual growth rate in the DRC and Zambia is a by-product of copper of seven per cent (BGS World Mineral Statistics Database). Global cobalt mine production in 2017 This profile provides an overview of the geological amounted to nearly 139 000 tonnes (Brown et al., potential for cobalt in the UK. It forms part of a 2019). The Democratic Republic of Congo (DRC) series on raw materials used in decarbonisation dominates with a share of 59 per cent of the total in technologies that may occur in the UK, and is 2017. Other significant current producers include based on publically available data and information. New Caledonia (seven per cent), China (6%), 1 extraction, while cobalt production in most other There has been no modern exploration for countries is a by-product of nickel mining. For cobalt in the UK, although a few reconnaissance example, in Cuba and New Caledonia cobalt investigations of polymetallic mineralisation is a by-product of nickel extraction from laterite enriched in cobalt or with potential for cobalt deposits, while cobalt produced in Canada, Russia enrichment have been undertaken. For example, and China is from magmatic sulfide deposits. the BGS undertook diamond drilling to investigate Cobalt is produced as the primary commodity from cobalt-bearing silver ores at Alva and Hilderston in only a single operating mine, which is located at central Scotland (Hall et al., 1982; Stephenson et Bou Azzer in Morocco (Bouabdellah et al., 2016). al., 1983). There is currently no mine production of cobalt in the UK and there are no deposits in which Cobalt can be found in economic concentrations cobalt reserves or resources have been reported. in three principal deposit types: stratiform sediment-hosted copper-cobalt deposits; nickel- UK occurrences cobalt laterite deposits; and magmatic nickel- copper (-cobalt-platinum-group element) sulfide In south-west England cobalt was recovered from deposits (Naldrett, 2004; Mudd et al., 2013). nine mines from the mid-18th century to the 19th Cobalt is also concentrated in a variety of other century, with a total production of a few hundred geological settings and deposit types, some of tonnes of ore (Rollinson et al., 2018). The mines which were sources of cobalt in the past (Slack with known production are: Wheal Sparnon near et al., 2017). These include: polymetallic cobalt- Redruth; Pelyn Wood Mine near Lostwithiel; Tretoil rich veins; iron oxide-copper-gold deposits; Wood Mine near Lanlivet; Trugo Mine near St. volcanogenic massive sulfide deposits; skarn Columb; Dolcoath and East Pool near Camborne; and replacement deposits; cobalt-copper-gold Great Dowgas and St. Austell Consols near St. deposits in metasedimentary rocks; black shale- Stephen; and Pengreep, near Gwennap. Wheal hosted nickel-copper-zinc-cobalt deposits; and Sparnon had the most significant production, from Mississippi Valley-type zinc-lead deposits. Most a so-called ‘cobalt lode’, which was mined solely deposits in these environments have produced for cobalt. The ore was mainly roasted to produce relatively small amounts of cobalt, commonly as cobalt oxides for use in the pottery industry a by-product of mining copper, nickel, silver, lead (Jenkin, 1979; Rollinson et al., 2018). Cobalt at or zinc. Significant concentrations of cobalt also these mines in Cornwall is associated with lead, occur on the sea floor in iron-manganese-rich zinc, silver, uranium, antimony, manganese, iron, nodules and crusts, although to date no cobalt bismuth and nickel in late mineralised fractures has been extracted from these on a commercial known as cross-courses, which cut across the scale. main copper and tin orebodies (Rollinson et al., 2018). Cobalt-rich mineralisation has also been Cobalt occurs in a wide variety of minerals reported in copper-lead-zinc-silver ores associated commonly in association with iron, nickel, copper with the Wheal Lushington mines at Porthtowan and sulfur (Petavratzi et al., 2019). In the surficial near St Agnes (Rollinson et al., 2018). Mineralogical environment cobalt also forms several oxide, studies have identified abundant cobaltite (CoAsS) hydroxide and carbonate phases. and subordinate erythrite (Co3(AsO4)2.8H2O) in these ores. UK production and resources In Cheshire, small amounts of cobalt were Cobalt occurs as a minor constituent of base metal recovered from copper deposits in Triassic ores in several parts of the UK (Figure 1). However, sandstones at Alderley Edge in the early 19th where these ores were mined in the past copper, century and at Clive in Shropshire (Bateson et al., lead and zinc, and locally silver and nickel, were 1982; Warrington, 2012). There is no information the main metals of interest. At a few abandoned on the amount of ore extracted or metal produced mines in south-west England, north Wales, central from the mines in this district prior to 1857 Scotland and Cheshire a few hundred tons of (Warrington, 1981). In one of the mines at Alderley polymetallic ores including cobalt were mined, Edge, cobalt is concentrated in a series of north– mainly in the 18th and 19th centuries. south trending faults. This mine has recently been 2 Cenozoic Quaternary, Neogene, Palaeogene Mesozoic 60°N Cretaceous Jurassic Triassic Occurences with Deposit Palaeozoic cobalt production type 59°N Vein Permian Stratiform sediment- hosted copper Carboniferous Mississippi Valley lead-zinc Devonian Occurences with no Deposit cobalt production type Silurian 58°N Vein Ordovician Mesothermal gold Cambrian Mississippi Valley lead-zinc Precambrian Unclassified Neoproterozoic 57°N Palaeoproterozoic Coille- Archaean Craignure bhraghad Silver Glen Igneous rocks 56°N Intrusive Hilderston Volcanic 55°N Tynebottom Lake District 54°N Foel Hiraddug Great Orme Alderley Edge 53°N Dolgellau gold belt Central Wales orefield 52°N 51°N 0 100 200 km Cornwall 50°N 10°W 9°W 8°W 7°W 6°W 5°W 4°W 3°W 2°W 1°W 0° 1°E 2°E Contains Ordnance Survey data © Crown copyright and database right 2020 Figure 1 Location of the principal cobalt occurrences in the United Kingdom. 3 named the Cobalt Mine but there is no data on et al., 1983). The Coille-bhraghad and Craignure the cobalt content of the ores nor on the scale of copper mines, near Inverary in western Scotland, past production (Derbyshire Caving Club, 2019). are reported to have also produced nickel-bearing Warrington (2010) described asbolane minerals, pyrrhotite and pentlandite, which 4+ ((Ni,Co)2-xMn (O,OH)4.nH2O) as common, contained trace levels of cobalt. These deposits gersdorffite (NiAsS) as uncommon and erythrite as are associated with a suite of mafic intrusions in rare at Alderley Edge. Neoproterozoic Dalradian metasedimentary rocks (Coats et al., 1982). In the Lake District ores from Scar Crag and Dale Head North have high reported cobalt contents In the Central Wales Orefield cobalt is a (Stanley and Vaughan, 1980 and 1982; Ixer et minor component of early polymetallic vein al., 1979). Cobalt extraction was attempted in mineralisation, which is noted for its varied the mid-19th century at Scar Crag, which was mineralogy (Mason, 1997). The main mining also called the ‘cobalt mine’, but this was never activity here focussed on lead, zinc, copper and successful (Postlethwaite, 1913). Cobalt is silver. Cobalt occurs in various cobalt-nickel associated with a chalcopyrite-pyrite-arsenopyrite minerals such as cobalt pentlandite ((Co,Ni,Fe)9S8), 2+ 3+ assemblage and is incorporated in skutterudite siegenite (CoNi2S4), linnaeite (Co Co S4) and ((Co,Ni)As3-x) and sulfarsenides, such as alloclasite millerite (NiS). Cobalt pentlandite has been (Co1-xFexAsS), glaucodot ((Co0.50Fe0.50)AsS) and recorded at several mines including: Erglodd, cobaltite (Ixer et al., 1979; Stanley and Vaughan, Brynyrarian, Loveden, Ystrad Einion, Esgairhir, 1982). A silver-nickel-cobalt mineral association Esgairfraith and Nantycagl (National Museum has been described from the disused lead mine Wales, 2019a). In North Wales cobalt and nickel at Tynebottom, Garrigill, near Alston in the North sulfides occur in epigenetic copper ores in Pennine Orefield (Ixer and Stanley, 1987). These Carboniferous dolostone at the Great Orme ores occur in the Brigantian age (Carboniferous) Mine, near Llandudno (Ixer and Stanley, 1996; Tynebottom Limestone, which rests on the Whin National Museum of Wales, 2019b). However, Sill in this area. Several cobalt-bearing minerals cobalt production in Wales is only known from have been reported from this locality, including Foel Hiraddug (also known as Moel Hiraddug) cobalt and nickel arsenides, sulfarsenides and near Dyserth, located about 30 kilometres sulfantimonides. Small amounts of nickel-cobalt east of Llandudno. Here the cobalt occurs as mineralisation comprising niccolite (NiAs) asbolane, a cobalt hydroxide, associated with accompanied by ‘smaltite’ (possibly skutterudite manganese oxides and hematite in a clay-filled or cobaltite) have been recorded with copper ores fissure hosted in limestone of Carboniferous age. in the Bonser vein and in the Paddy End section In addition to working for hematite and pyrite, of the mines near Coniston in the Lake District cobalt and nickel were also produced at this site.