Barytes (barium sulphate, BaSO4), alsoreferred to as barite or baryte, is the most
abundant and economically important bariummineral produced in the UK and worldwide.Witherite (barium carbonate, BaCO3) wasmined commercially in England in the northernPennines until 1969; worldwide economicdeposits of witherite are rare.
Barytes, when pure, contains 58.8% barium and41.2% sulphate and with a specific gravity (SG)of 4.5 it is often referred to as ‘heavy spar.’Inclusions of other minerals may reduce (or inthe case of metallics increase) the SG, but ahigh density, chemical inertness and wide-spread occurrence are the properties that arevalued for barytes’ most important applicationas a weighting agent in drilling fluids. Colourand chemical purity are important propertieswhen considering the suitability of barytes fornon-drilling applications.
Barytes is produced in England and Scotland.In England barytes is now only produced as aby-product of fluorspar mining and processing.In Scotland, barytes is extracted as the solemineral from the Foss Mine near Aberfeldy. Theprincipal planning issues associated withbarytes production in England are identical to
the more economically important mineralfluorspar (CaF2). The factsheet on Fluorspar
should be consulted for more detailed informa-tion on these issues. In Scotland, the principalplanning issues associated with barytes extrac-tion relate to the location of the deposits inareas designated for their landscape quality.
Demand
The most important use of barytes, accountingfor about 83% of total world consumption, is asa weighting agent to increase the density ofdrilling fluids, principally for oil and gas explo-ration. Finely ground barytes is added to thedrilling fluid and its function is to confine highformation pressures due to oil, gas and waterliberated by drilling and thus prevent‘blowouts’. The suitability of barytes for this pur-pose is based on a combination of properties, inaddition to a high SG (minimum 4.2). Theseinclude low abrasiveness, chemical inertness, anon-magnetic character, and being clean andeasy to handle and grind. Barytes is also cheapand readily available and although alternativesare available, some of which are used for spe-cialised applications, barytes is the standardweighting agent used in drilling fluids through-out the world. Demand is essentially a functionof oil and gas exploration activity. Most of thebarytes produced and imported into the UK isfinely ground for use in hydrocarbon explo-ration mainly on the UK Continental Shelf.
Non-drilling applications of barytes are com-paratively small, although still importantbecause of their higher value. High puritygrades of bartyes with fine and controlled parti-cle sizes are used as fillers in marine and indus-trial paints, in brake lining/friction materialsand in plastics. A specialised use of barytesbased on its high density and ability to absorbradiation, is as an aggregate in dense concretefor shielding applications in the nuclear indus-try and hospital radiation departments.
Supply
Over 80% of total barytes sales in the UK ofsome 61 000 tonnes in 2004 were derivedfrom the Foss Mine, near Aberfeldy inScotland. The output is mainly used in drilling
1
Mineral Planning Factsheet
Barytes
Barytes extraction,Foss Mine, Scotland.©M-I Drilling Fluids UK
This factsheet pro-vides an overviewof barytes supplyin the UK. It is oneof a series on eco-nomically impor-tant minerals thatare extracted inBritain and is pri-marily intended toinform the land-useplanning process.
January 2006
Barytes
Barytes 2
fluids, although some is used as an aggregatefor radiation shielding. Following the closureof two small open-pit barytes workings in theNorthern Pennine Orefield, at Closehouse inDurham in 2000 and Silverband in Cumbria in2002, production in England is now confinedto the Southern Pennine Orefield in the PeakDistrict. The mineral is derived as a by-productof processing fluorspar ore at the CavendishMill, near Stoney Middleton in the PeakDistrict National Park. Output is dependent onthe barytes content of the fluorspar ore, whichvaries depending on the deposit beingworked. Production was some 12 000 tones in2004, most of which was sold locally for value-added processing by fine grinding (micronis-ing) for filler applications in paints and plas-tics. Some was sold for use in oil well drillingfluids.
Trade
The UK has been a significant net importer ofbarytes for many years. Imports are mainlyused in drilling fluids, although a proportion isalso imported for fine grinding for filler applica-tions. Imports have been in the range 60 000 to210 000 t/y over the last 20 years, the level ofimports essentially reflecting hydrocarbonexploration activity on the UK ContinentalShelf. However, in recent years imports havedeclined due to a general decrease in explo-ration activity (See Table 1). Exports are modestand have been between 5 000 and 10 000tonnes in most years. However, since 2000,exports have reportedly been much larger.
Consumption
Barytes consumption in the UK mainly reflectsthe level of hydrocarbon exploration activity onthe UK Continental Shelf. Following the discov-ery of hydrocarbons in the North Sea in theearly 1970s consumption of barytes increasedto a peak of 260 000 tonnes in 1990–91, themajor proportion of which consisted of imports.More recently consumption has been in therange 100 000 to 200 000 t/y due to a decline inexploration activity (Figure 2). Although UK oiland gas production is in decline, the largeincreases in the price of oil and gas experi-enced in 2005 may stimulate more explorationactivity offshore as smaller fields become moreviable. Consumption of barytes for fine grind-ing for filler applications is about 20 000 t/y.Some of the material is exported.
Economic importance
Barytes production in Britain generates onlymodest amounts of direct revenues of about £3 B
ary
tes
Mineral Planning Factsheet
Imports Exports
Tonnes £thousand Tonnes £thousand
1996 82 656 3 938 5 433 1 270
1997 138 499 5 712 9 438 1 847
1998 98 480 4 394 6 579 1 384
1999 65 356 2 833 8 148 1 516
2000 57 244 2 845 28 472* 2 843
2001 77 153 3 431 58 952* 3 880
2002 74 843 3 117 37 759* 3 163
2003 56 867 2 406 69 094* 3 837
2004 63 924 2 733 25 160* 2 887
*These figures are believed by the BGS to be too high
Table 1 UK: Imports and exports of barytes,
1996-2004. Source: HM Revenue & Customs.
Barytes
0
50
100
150
200
250
1 945 195 0 1955 19 60 196 5 1 970 19 75 1 980 1 985 199 0 1 995 20 00
ImportsProduction
Thousand tonnes
Figure 1 UK: Production and imports of
barytes, 1945–2004. Source: UnitedKingdom Minerals Yearbook, BGS.
million. The mineral is, however, essential forhydrocarbon exploration and thus contributesto maintaining the UK’s economically importantoil and gas production. Barytes recovery is alsoan integral part of the economic viability offluorspar mining and processing in the PeakDistrict. Moreover, the high purity productrecovered is further processed by fine grindingin Derbyshire for filler applications yieldingadditional sales of £1.5 to £2 million.
Structure of the Industry
M-I Drilling Fluids UK, a subsidiary of the USA-based global drilling fluids manufacturer M-ISWACO, operates the Foss Mine in Scotlandand also has title to the nearby world-classDuntanlich barytes deposit. Annual productionfrom Foss Mine is about 50 000 tonnes, and thebroken ore is sent to either Aberdeen (where itis finely ground for use in oil explorationdrilling as a weighting agent) or to GreatYarmouth. With CIF1 costs representing 80% ofthe cost of delivered drilling grade barytes(US$65-70 per tonne) the location of thedeposit and relatively short transport distanceto Aberdeen make Foss barytes locally compet-itive.
Glebe Mines Ltd, a privately-owned company,is now the only producer of barytes inEngland following the closure of two smallopen-pit operations in the northern Penninesin 2000 and 2002. The company operates theCavendish Mill, near Stoney Middleton,where barytes is a by-product of processingfluorspar ore. Some of the barytes is sold intothe drilling fluids market but most is sold toViaton Industries Ltd, a Derbyshire-basedcompany specialising in the fine grinding(micronising) of both domestically producedand imported barytes for filler applications.The Cavendish Mill supplies about half of thecompany’s barytes requirements.
Resources
Barytes has been worked in many parts of theUK. The most important deposits are nearAberfeldy in Perth and Kinross in Scotland andin the Southern and Northern Pennine ore-fields. Significant production was also formerlyrecorded in other areas, notably Shropshire,the Lake District, south Devon and centralScotland. In England, barytes occurs mainly asvein infillings in faults, which cut a variety ofrock types. The most important are limestonesof Carboniferous age but veins cutting slates,mudstones and volcanic rocks of Precambrian,Lower Palaeozoic and Devonian age have alsobeen worked. Intense alteration of limestonewall rocks has also led locally to the formationof replacement deposits adjacent to majorveins in the Northern and Southern Pennines.However, vein and replacement deposits tendto be small.
In contrast, bedded or stratabound deposits aremuch larger. Foss Mine (located in the BenEagach Schist Formation) works a strataboundbaryte deposit near Aberfeldy in Scotland,which occurs in highly, folded Precambrian(Proterozoic) metasedimentary rocks, and is themajor source of barytes in the UK. Much largerresources of barytes have been proved at thenearby Duntanlich deposit, which is also geo-logically much less complex and would be easi-er to mine. Dalradian Supergroup rocks thathost barytes deposits near Aberfeldy extend forover 200 km across central Scotland from Islayin the south west to Portsoy in the north east.
Barytes3
Bary
tes
Mineral Planning Factsheet
Barytes
0
50
100
150
200
250
300
1974 1979 1984 1989 1994 1999 2004
Tho
usa
nd
ton
nes
Figure 2 UK: Apparent consumption of
barytes, 1974–2004. Source: BGS. Exports esti-mated for 2000–2004.
1 Cost, Insurance, Freight — CIF is the term used to indicate
total value of a shipment. This compares with Free On Board
(FOB) where the sellers commitments end when the ship-
ment is placed onto the transport carrier, thus FOB is usually
the value of the commodity only.
Barytes 4
Indications of barytes mineralislation havebeen found at a number of localities along thiszone. The possibility that similar styles of min-eralisation could be found in England cannot todiscounted.
Reserves
Permitted reserves at the Foss Mine in Scotlandare sufficient for about four or five years produc-tion, after which the UK will have no majordomestic source of barytes. The nearbyDuntanlich barytes deposit has an inferredresource of 13 million tonnes, with measuredresources of high-quality barytes of 7 milliontonnes. This would be sufficient to meet the UK’sapparent consumption of barytes for manydecades, and would bring to an end the currentneed to import barytes. Measured resources ofbarytes at Duntanlich are larger than the esti-mated 6.7 million tonnes that have been extract-ed from all UK sites since records began in 1876.
In England, barytes extraction ceased in theNorthern Pennines in 2002, due to economicfactors. All production of barytes in England isnow as a by-product of fluorspar mining andprocessing in the Southern Pennine Orefield.Reserves of barytes are, therefore, confined tofluorspar deposits, where the barytes content isvariable depending on location within the ore-field. (See Factsheet on Fluorspar).
Relationship to environmental designations
The Foss Mine and the Duntanlich deposit arelocated in the Tummel National Scenic Area(NSA). Bartyes mineralisation of current eco-nomic interest in England is confined to theSouthern Pennine Orefield, most of which islocated in the Peak District National Park.
Extraction and processing
At Foss Mine the ore is of sufficient purity to beextracted from underground workings and sentfor further grinding at Aberdeen without anyupgrading.
The typical feed grade to the Cavendish Millcontains 28% CaF2, 8–9% BaSO4 and <1% Pb.Extraction is geared towards maximising the
recovery of fluorspar, which is the most valu-able product. Barytes is recovered by a combi-nation of heavy media separation and frothflotation to produce a final product grading92–95% BaSO4. In addition to fluorspar, a lead(galena) flotation concentrate is also producedwhich is sold locally.
By-products
There are no by-products of barytes extractionin Scotland. Barytes extraction in the PeakDistrict is itself a by-product of fluorspar min-ing and processing.
Mineral Planning Factsheet
Barytes
Aberdeen
Edinburgh
Manchester
Nottingham
CardiffLondon
Newcastle
Foss Mineproduces barytesas the sole product
Northern Pennnine OrefieldProduction ceased in 2002
Southern Pennnine Orefieldproduces barytes as aby−product of fluorsparmining and processing
Viaton IndustriesWirksworth
Great Yarmouth
Major Orefield
Legend
Mine
Open pit
Duntanlich, majorunworked deposit
Figure 3 Barytes producing areas.
Alternatives/recycling
Small quantities of hematite and ilmenite areused as alternatives to barytes as weightingagents in drilling fluids. Calcium carbonate(limestone/marble) may also be used wherewells are relatively shallow. New developmentswith synthetic-based fluids allow the cuttings tobe discharged offshore whilst the drilling fluidis returned to a shore base for remediation andre-use. This is resulting in an overall reductionin new barytes consumption per metre drilled.
Effects of economic instruments
Barytes is not subject to the Aggregates Levy.
Planning issues
The principal planning issue is the location ofbarytes resources in national landscape desig-nations, both in Scotland and England. In themost important case in Scotland, this has pre-vented mineral development, even where theproposed extraction method was by under-ground mining.
The Foss Mine and its associated surface oper-ations cover an area of about 15 ha and fallentirely within the Tummel NSA. The much larg-er Duntanlich deposit, some 6 km to the east,also lies in the same NSA. A planning applica-tion to develop an underground mine atDuntanlich with an output of 200 000 t/y wasrefused in 1992. The application was the subjectof a public inquiry in 1993, but the appeal wasdismissed in 1994. The Court of Session upheldthis decision in 1996 on the grounds that the
economic benefits did not outweigh the envi-ronmental disadvantages. There were addition-al concerns about providing access for lorriesto the trunk road system. Although the compa-ny may submit a revised planning application,there remains the likelihood that this world-class deposit of barytes will never be worked.
Further information
Barytes Profile. http://www.mineralsuk.com
The Barytes Associationhttp://www.barytes.org/
Authorship and acknowledgements
This factsheet was produced by the BritishGeological Survey for the Office of the DeputyPrime as part of the research project ‘ODPM-BGS Joint Minerals Programme.’
It was compiled by David Highley and KevinBonel, with the assistance of Don Cameron andDeborah Rayner.
The advice and assistance of the ODPM, andthe barites industry is gratefully acknowledged.
Mineral Planning Factsheets for a range ofother minerals produced in Britain are availablefor download from www.mineralsUK.com
© Crown Copyright 2006
Unless otherwise stated all illustrations andphotographs used in this factsheet are BGS©NERC. All rights reserved.
Barytes5
Bary
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Mineral Planning Factsheet
Barytes