MINERAL COMMODITIES OF NEWFOUNDLAND AND …Mineral Commodities of Newfoundland and Labrador Zinc and Lead Foreword This is the first in a series of summary publications covering the

MINERAL COMMODITIES OFNEWFOUNDLAND AND LABRADORMINERAL COMMODITIES OFNEWFOUNDLAND AND LABRADOR

ANDZINC LEADANDZINC LEAD

Mines Branch

Mineral Commodities ofNewfoundland and Labrador

Zinc and LeadForeword

This is the first in a series of summary publications covering the principal mineral commodities of the Province. It’s pur-pose is to act as a source of initial information for explorationists and to provide a bridge to the detailed repository of

information that is contained in the maps and reports of the provincial and federal geological surveys, as well as in numerousexploration-assessment reports. The information contained in this series is accessible via the internet at the Geological Surveyof Newfoundland and Labrador web site http://www.nr.gov.nl.ca/mines&en/geosurvey/

Publications in the SeriesZinc and Lead (Number 1, revised 2008); Nickel (Number 2, revised 2008);Copper (Number 3, revised 2007); Gold (Number 4, revised 2008); Uranium in Labrador (Number 5, 2008)

Additional Sources of Information

Further information is available in the publications of the geological surveys of Newfoundland and Labrador and Canada.The Geological Survey of Newfoundland and Labrador also holds a considerable inventory of exploration-assessment files

available for onsite inspection at its St. John's headquarters and for download via the Geological Survey of Newfoundland andLabrador web site http://www.nr.gov.nl.ca/mines&en/geosurvey/. Descriptions of individual mineral occurrences are availablethrough the provincial Mineral Occurrence Database System (MODS), which is accessible from the Survey’s web site. Up-to-date overviews of mining developments and exploration activity targeting copper are available on-line at http://www.nr.gov.nl.ca/mines&en/

Contact AddressesGeological Survey of Newfoundland and Labrador Geological Survey of CanadaDepartment of Natural Resources 601 Booth StreetP.O. Box 8700 Ottawa, ON, CanadaSt. John’s, NL, Canada K1A 0E8A1B 4J6 Tel. 613.995.4342Tel. 709.729.3159 Fax 613.943.0646Fax 709.729.4491 Long distance (Canada and USA) 1.888.252.4301http://www.nr.gov.nl.ca/mines&en/geosurvey/ http://www.NRCan.gc.ca/gsc/

NOTE

The purchaser agrees not to provide a digital reproduction or copy of this product to a third party. Derivative productsshould acknowledge the source of the data.

DISCLAIMER

The Geological Survey, a division of the Department of Natural Resources (the “authors and publishers”), retains the soleright to the original data and information found in any product produced. The authors and publishers assume no legal lia-

bility or responsibility for any alterations, changes or misrepresentations made by third parties with respect to these productsor the original data. Furthermore, the Geological Survey assumes no liability with respect to digital reproductions or copiesof original products or for derivative products made by third parties. Please consult with the Geological Survey in order toensure originality and correctness of data and/or products.

Compiled by R.J. Wardle, 2000Reprinted with minor revisions, 2008

Front Cover: Colloform sphalerite ore, Daniel’s Harbour mine.

Introduction

Zinc was the most important non-ferrous metalliccommodity produced in Newfoundland between

1928 and 1990. During this period, 2.3 million tonnesof the metal were produced with an in situ value ofUS$3.1 billion, using present day prices. Lead, apartfrom some early ventures, was generally producedonly as a by-product of other mining operations for atotal production of 1.22 million tonnes at a presentday in situ value of US$556 million.

The two most important geological environmentsfor zinc and lead mineralization in Newfoundland arethe carbonate platform rocks of western Newfound-land, which host Mississippi Valley-type (MVT)deposits, and the volcanic terranes of central New-foundland, which host numerous volcanogenic mas-sive sulphide (VMS) deposits. Lead, and to a lesserextent zinc, also occur in a number of vein-hosted epi-genetic occurrences that locally formed the basis for19th century mining operations, but which are gener-ally uneconomic in today's markets.

The first recorded production of lead in New-foundland was from vein deposits at the La MancheMine of Placentia Bay in 1855. Attempts were madeto develop other mines between 1860 and 1885; how-ever, these were all based on small epigenetic veinsand none managed any sustained period of productionor profitability.

Modern mining of zinc and lead began in 1928with the development of the Buchans volcanic-hosteddeposits located in central Newfoundland (Figure 1).Further discoveries followed, and theBuchans operations remained inproduction until their eventualdepletion in 1984. In the mean-time, exploration in the westernNewfoundland carbonate plat-form had led to the discovery in1963 of the Daniel's Harbourzinc deposit. This came into pro-duction in 1975 and closed in 1990,again following depletion of the orereserves.

Although there is currently no production of zincor lead in the Province, there remains considerablepotential for future discoveries.

Carbonate-Hosted MineralizationEnvironments

The principal mineralization envi-ronments of this type are found

in the carbonate rocks of theHumber Zone that form thewestern margin of the New-foundland Appalachians. Threerock units host zinc–lead miner-alization in the Humber Zone,

the most important of which isthe Cambro-Ordovician platformal

carbonate sequence that stretches fromthe Port au Port Peninsula in the south to the top of theGreat Northern Peninsula (Figure 2). The predomi-nant mineralization consists of sphalerite–galena andpyrite filling secondary voids as a replacement of car-bonate beds and as the matrix to collapse breccias.

1

Mineral Commodities of Newfoundland and Labrador Zinc and Lead

Zinc was themost important non-

ferrous metallic commodityproduced in Newfoundland duringthe period 1928 to 1990 when 2.3

million tonnes of the metalwere produced.

Figure 1. The Lucky Strike Glory Hole S the firstBuchans Mine.

Generally, this mineralization is considered to be ofMississippi Valley-type (MVT) and comparable toother deposits of this type found in the western plat-formal sequences of the Appalachian Orogen (e.g.,

the lead and zinc deposits of Tennessee). Mineraliza-tion is found throughout the sequence but predomi-nantly within the Port au Port and St. George groups(Figure 3). Sphalerite is the dominant ore mineral and

2


ZINC and LEAD OCCURRENCESof NEWFOUNDLAND

Gander

Grand Falls

Marystown

Port Aux Basques

DUNNAGEZONE

HUMBER ZONE

GANDER ZONE

AVALON ZONE

St. John’s

INTRUSIVE ROCKS

Ordovician Devonian intrusions–

Neoproterozoic Cambrian intrusions–

Devonian to Carboniferous sedimentary rocks

Silurian sedimentary and volcanic rocks

OVERLAP SEQUENCES

AVALON ZONENeoproterozoic to Ordovician

Subaerial marine sedimentaryrocks

–

Mafic and felsic volcanic rocks

DUNNAGE & GANDER ZONESCambrian to Silurian

Marine clastic and volcanic rocks

Ophiolitic rocks

Metasedimentary rocks andmigmatite

Platformal carbonate rocks

Clastic and metasedimentaryrocks

Basal clastic, carbonate andvolcanic rocks

Gneisses and granites

Neoproterozoic to OrdovicianHUMBER ZONE

St. Lawrence

Daniel’sHarbour

Goodyear

Lead Cove

Strickland #6 Trench

Galena #1 vein

Baraswayde Cerf

Silvercliff

TurnersRidge

Silverdale

Great Northern Peninsula

Port au PortPeninsula

Bonne Bay

Round Pond

Baie Verte Peninsula

Fig. 6

Winter Hill

Trapper

Zn-Pb mineral occurrences

Maj

or p

ast-p

rodu

cing

min

eSi

gnifi

cant

und

evel

oped

de

posit

Sign

ifica

nt o

ccur

renc

eSe

lect

ed m

inor

oc

curre

nce

Carbonate-hosted

Clastic-hosted

Volcanic-hosted

Granite-related-vein-hostedNon-igneous vein-hosted

Meso Neoproterozoic–

Neoproterozoic Ordovician–

Figure 2. Simplified geological map of Newfoundland showing location of major zinc and lead occurrences.

was preceded by the development of a secondary por-osity in association with formation of pseudobreccia.The latter is a replacement product in which “frag-ments” of earlier dolomitized limestone are left float-ing in a matrix of secondary sparry dolomite (Figure4). Other true breccias in the vicinity of the depositsare related to solution collapse, probably in responseto the local emergence of the platform and consequentkarstification of the carbonate rocks below a regionalunconformity.

The single major example of an MVT-typedeposit was at Daniel's Harbour, where about 7 mil-lion tonnes of zinc ore, at an average grade of 7.8%zinc, were mined between 1975 and 1990. Thedeposit consisted of numerous ribbon-like orebodieshosted by pseudobreccia. The orebodies were local-ized on the margins of structural depressions, inter-preted as solution collapse structures that formed dur-ing emergence, closely associated with contempora-neous faulting (Figure 3). Sphalerite was depositedtogether with hydrothermal dolomite after significantburial. Reactivated faults and veins served as conduitsfor warm, saline brines that carried the zinc.Numerous other zinc showings outcrop in theDaniel’s Harbour area, including the Trapperprospect, where mineralization has been encounteredin a widely spaced drilling program. The only othersignificant deposit is at Round Pond, where 152 400tonnes of 2.5% Zn have been identified in chertydolomite breccias and pseudobreccia of the BoatHarbour Formation (St. George Group), locally inassociation with bitumen-rich zones and other zinc–lead occurrences.

Numerous other minor occurrences are foundthroughout the stratigraphic sequence of the carbonate

platform. These include vein-hosted and void-fillsphalerite–galena occurrences in sparry and fine-grained dolomite of the Cambrian Port au Port Groupon the tip of the Great Northern Peninsula, and nearCorner Brook in the south. These are too numerous tobe all shown on Figure 2 but are depicted schemati-cally in Figure 3.

A different style of mineralization is found with-in the brecciated and reefoid Carboniferous rocks that

3


limestone

limestone

pseudobrecciapseudobreccia

SEDIMENT INFILLOF PALEO-DEPRESSION

collapsebreccia

Aguathuna Fm.

CatocheFm.

ZINC ORE ZONE

PREDOMINANTLYCLASTIC ROCKS

PREDOMINANTLYCARBONATE ROCKS

zincoccurrence

–lead

ALLOCHTHONOUSSEQUENCE

MAINLANDSANDSTONE

TABLE HEADGROUP

ST. GEORGEGROUP

PORT AU PORTGROUP

LABRADORGROUP

PRECAMBRIAN BASEMENT

OR

DO

VIC

IAN

CA

MB

RIA

N

1000

500 m

0

50 m

0 100 m

Figure 3. Setting ofDaniel’s Harbour-typezinc–lead mineraliza-tion in relation topaleodepressions andpseudobreccia.Column at left showsstratigraphic positionof Daniel’s Harbourand other MVT zinc–lead occurrences (afterLane, 1984).

Figure 4. Daniel’s Harbour ore. Early, grey, bur-rowed dolostone has been replaced by yellow spha-lerite and white dolomite, locally enclosing suspend-ed fragments of dolostone in pseudobreccia texture.

overly the Cambro-Ordovician sequences on the Portau Port Peninsula. The basal Carboniferous rocksoccupy north-trending paleokarst valleys and containopen-space fillings of galena and sphalerite associat-ed with marcasite, calcite, and locally barite andstrontianite/celestite gangue. The underlying Cambro-Ordovician carbonates also contain similar mineral-ization in veins and vugs that at least locally have aspeleothem character and may thusbe karst related. Therefore, thelead-rich mineralization in thisarea may be of predominantlyCarboniferous or younger age.Examples of this style of min-eralization are found at theGoodyear and Lead Cove pros-pects (Figure 2). The latter is note-worthy for an unsuccessful attempt, ca. 1874, to minelead. Veins of similar style, and age of mineralization,are known in other areas of the Port au Port Peninsulaand to the east.

A third carbonate-hosted environment is found inthe Silurian Sops Arm Group of western White Baywhere brecciated dolomite at the base of the sequenceis host to the Turners Ridge deposit (Figure 2), con-taining 200 000 tonnes of between 3 and 4% lead inthe form of galena, and in association with sphaleriteand pyrite mineralization. Brecciation is likely relatedto thrusting of this part of the Sops Arm Group overCarboniferous rocks of the Deer Lake Basin. As thegalena and sphalerite postdate the brecciation, it isprobable that the mineralization is Carboniferous andderived from fluids expelled from the Deer LakeBasin.

A Paleoproterozoic equivalent of MVT mineral-ization occurs in the Ramah Group of northernLabrador (Figure 5) where the Reddick BightFormation dolomite is host to a number of smallsphalerite–galena ± pyrite occurrences associatedwith secondary void-fill texture.

Volcanic-Hosted MineralizationEnvironments

For zinc and lead mineralization, this environmentis largely restricted to the volcanic terranes of the

Dunnage Zone in central Newfoundland (Figures 2and 6) but is also known in the Neoproterozoic vol-canic rocks of the western Avalon Zone (Figure 2).The Dunnage Zone represents a collage of Cambrian

to Mid-Ordovician island-arc terranes, which weremostly constructed on a substrate of ophiolitic ocean-ic crust, and structurally juxtaposed during Late Or-dovician to Early Silurian ocean closure. The junctionbetween the western and eastern margins of this oceanis generally termed the Red Indian Line (Figure 6).

The arc terranes comprise variable proportions ofmafic and felsic volcanic rocks in

association with thick epiclasticsequences and have beengrouped into back-arc, primi-tive-arc, mature-arc and conti-nental-rift (back-arc?) associa-

tions. Zinc–lead mineralizationis generally associated with the

mature-arc and continental-rift asso-ciations, but also with mixed mafic/felsic sequencesin the primitive-arc association. In contrast, the back-arc and mafic-dominated primitive-arc sequencestend to be copper dominated; however, deposits inthese sequences commonly contain zinc and lead assecondary commodities, e.g., in the Betts Cove,Whalesback and Little Deer mines of Notre DameBay (see the companion summary on Copper).Mineral assemblages are typically polymetallic, rang-ing from Zn–Pb–Cu–Au–Ag to Zn–Pb–Ag, lead andzinc becoming increasingly dominant toward thesouth, possibly reflecting the greater influence of con-tinental crust in that direction.

Mineralizing environments are generally thoseassociated with the development of volcanogenicmassive sulphide (VMS) deposits and include geneti-cally related stringer-stockwork, massive sulphide,and debris-flow deposits.

The Dunnage Zone is conveniently divided into anumber of belts, as shown on Figure 6. The EarlyOrdovician Buchans–Roberts Arm belt is character-ized by bimodal calc-alkalic volcanic rocks ofmature-arc character and is deformed into a series ofgenerally southeast-verging duplexes and thruststacks, locally associated with strong deformation.The most significant zinc–lead VMS occurrences arethose at Buchans in the southwest and Pilley's Islandin the northeast. The major source of production hasbeen the Buchans deposits, where five major orebod-ies were mined between 1928 and 1984 for a total of16.2 million tonnes at average grades of 14.51% zinc,7.56% lead, 1.33% copper, 1.37 g/t gold and 126.0 g/tsilver. In terms of the value of the metal produced,these rank as world-class deposits and underscore the

4


The single, majorcarbonate-hosted deposit

was at Daniel’s Harbour whereapproximately 7 million tonnesof zinc ore, at an average grade

of 7.8% zinc, were mined.

potential of the central Newfoundland volcanic ter-ranes. Most of the mineralization is associated withfelsic pyroclastic rocks and breccias, and conforms tothe classic Kuroko model for VMS deposits. Threedistinct ore types, termed “stockwork”, “in-situ” and“transported” have been mined at Buchans, the mostimportant being the in situ and transported types. Thetransported ores are perhaps better developed thananywhere else in the world, and consist of tongue-likedebris-flow breccia deposits (Figure 7).

The Pilley's Island deposit is a predominantlycopper–pyrite deposit that was originally mined for itspyrite content. However, it contains localized zinc-rich zones, e.g., the Bull Road occurrence, which hasyielded samples containing up to 45.9% Zn. Othersignificant zinc occurrences in the Buchans–RobertsArm belt include the Lake Bond deposit (geologicalresource of up to 1 325 900 tonnes grading 2.6% Znand 0.38% Cu), the Connell and Shamrock prospects,and the Skidder deposit, which contains 1 000 000tonnes of 2% Zn and 2% Cu.

5


Figure 5. Simplified geological map of Labrador showing location of significant zinc and lead occurrences.

Felsic volcanic andmetavolcanic rocks

Neoproterozoic toCambro-Ordovician

MesoproterozoicSedimentary and mafic volcanic rocks

Granitic plutons

Anorthositic plutons

Mafic plutons

PaleoproterozoicGranitic plutons

Metasedimentary and mafic volcanic rocks

Felsic volcanic rocks

Anorthositic plutons

Mafic plutons

Metasedimentary gneiss

Mixed orthogneiss and stronglyfoliated granitoid plutons

ArcheanVolcanic and metasedimentary rocksOrtho- and metasedimentarygneisses

Cover sedimentary rocks0 100 km

Smallwood Reservoir

Wabush/Labrador City

Churchill Falls

ZINC and LEAD OCCURRENCES of LABRADOR

NAIN PROVINCE

SOUTHEASTERNCHURCHILLPROVINCE

SUPERIORPROVINCE

MAKKOVIKPROVINCE

GRENVILLEPROVINCE

Ramah Group

GalenaLake

GreenPond

Flowers River Suite

Big Bight

Labrador

Trough

Teuva

Zn-Pb mineral occurrences

Sign

ifica

nt o

ccur

renc

e

Sele

cted

min

or o

ccur

renc

e

Carbonate-hosted

Clastic-hosted

Granite-relatedvein-hostedNon-igneous vein-hosted

BlueberryLake

Group

Florence Lakebelt

Hunt River belt

The Early Ordovician Tulks belt, located in rocks ofthe Victoria Lake Group south of the Red Indian Line,consists of strongly deformed felsic and mafic volcanicrocks and is host to several significant deposits. Thelargest is the Tulks East deposit, which contains 5 000000 tonnes of 1.5% Zn, 0.12% Pb, 0.24% Cu, 8.5 g/t Agand trace Au in the A zone, in addition to 230 000 tonnesof higher grade combined metals in the B zone. Thenearby Tulks Hill deposit contains an additional 720000 tonnes of 5.6% Zn, 2% Pb, 1.3% Cu, 41 g/t Ag and0.4 g/t Au. Other occurrences include the Hoffs Pond (1233 000 tonnes of 6.91% Zn, 1.06% Cu, 0.71% Pb, 16.8g/t Ag and 0.2 g/t Au) and Long Lake (560 000 tonnes16.0% Zn, 2.2% Cu, 1.3% Pb, 38 g/t Ag and 0.9 g/t Au)deposits, and the Daniel’s Pond prospect. The VictoriaMine deposit, although generally copper-rich, containszinc–lead-rich zones (e.g., the Jig Zone).

The Cambrian Tally Pond belt comprises similar,but less penetratively deformed, rocks of the VictoriaLake Group. The principal deposit is Duck Pond (oth-erwise known as Tally Pond), which when combinedwith the nearby Boundary deposit contains a geologicalresource of 6 350 000 tonnes of 6.3% Zn, 3.29% Cu,1.0% Pb, 63.5 g/t Ag and 0.82 g/t Au. Aur ResourcesInc. put the Duck Pond Mine into production inJanuary 2007 and the first shipment left the island inApril 2007. The plan for the current reserves is to mine

6


Major past-producing mine

Significant undevelopeddeposit

Significant occurrence

DUNNAGE ZONE PbOCCURRENCES

Zn-

Cambro-Ordovician volcanic belts

Metasedimentary belts

Granitoid plutons and youngercover rocks RED INDIAN

LINELakeBond

Shamrock

Pilley’sIsland

Notre DameBay

Buchans

Connell

Burnt Pond

Haven Steady

Duck (Tally)Pond

BoundaryHoffs Pond

Victoria Mine

Daniel’sPond

LongLake

TulksHill Tu

lks Belt

Tally

Pon d

BeltTulks East

Skidder

0 25 km

Figure 6. Simplifiedmap of the volcanicand metasedimentarybelts of the DunnageZone, centralNewfoundland. Forlocation, see Figure 2.

Figure 7. Buchans transported-ore breccia. Noteclasts of massive chalcopyrite yellow ore (Y) andsphalerite–galena black ore (B)


and mill 4.1 million tonnes ofore, at a rate of 1800 tonnes perday, over a projected mine lifeof 6.2 years. Based on theexisting reserves, the annualproduction is expected to be76 million pounds of zinc.Other significant occurrencesinclude the Burnt Pond andHaven Steady prospects.

A significant occurrencelying to the northeast ofthese belts is the PointLeamington deposit (Figure6). This is a large, low gradeCu–Zn massive sulphidedeposit that contains an inter-esting Zn–Au-rich zone.

In addition, there are a number ofZn–Pb-rich occurrences along the southern margin ofthe Dunnage Zone, the largest of which are theStrickland, Number 6 Trench and Barasway de Cerfprospects (Figure 2) characterized by sphalerite–gale-na–pyrite mineralization within Early Ordovician felsicvolcanic rocks. The Strickland prospect is estimated tocontain 260 000 tonnes at 5.6% combined Pb and Znand 195 g/t Ag. A separate copper zone is also present.

The Neoproterozoic rocks of the western Avalonlocally contain sphalerite–galena mineralization infelsic volcanic rocks, the principal occurrence beingthe Winter Hill prospect. Volcanic-hosted base-metalmineralization is otherwise atypical of the volcanicrocks of the Avalon Zone in Newfoundland.

Labrador is markedly deficient in VMS-stylemineralization. However, there may be potential forthis type of mineralization in the Archean FlorenceLake and Hunt River greenstone belts of easternLabrador, and in the Paleoproterozoic volcanic rocksof the Blueberry Lake Group of western Labrador(Figure 5).

Vein-Hosted MineralizationEnvironments

Early attempts to mine lead and zinc were directedat vein-hosted epigenetic deposits that can be di-

vided into non-igneous and granite-associated types.

Non-igneous types include the Silvercliff and LaManche prospects, located in fault-confined galena–

sphalerite veins in Neoprotero-zoic rocks of the AvalonPeninsula, as well as theSilverdale and Traverstownprospects of the Baie VertePeninsula located withinveins in Cambro-Ordovicianrocks. All of these were thetargets of unsuccessful min-ing attempts in the late 19thcentury. Zinc and lead alsooccur locally in associationwith gold-bearing veins ofcentral Newfoundland andthe Baie Verte Peninsula. InLabrador, non-igneous vein-

hosted prospects are presentwithin Paleoproterozoic shale–

sandstone sequences of theMoran Lake Group of eastern

Labrador (e.g., Green Pond prospect, Figure5), and the Labrador Trough of western Labrador(e.g., Galena Lake prospect, Figure 5).

Granite-related veins are found in, or adjacentto, various Siluro-Devonian granites in southernNew-foundland, e.g., the Galena Number 1 prospectlocated in a sulphide-bearing quartz vein within theBurgeo batholith, and various Pb–Zn–U and Pb–flu-orite veins in the St. Lawrence peralkaline granite(Figure 2). One of the latter in the Lawn area wasalso the target of an early attempt, (ca. 1860), tomine argentiferous galena. In Labrador, the FlowersRiver Suite (Nain Province) hosts minor spha-lerite–galena– pyrite mineralization in associationwith veinlets and alteration zones in peralkalinegranite and volcanic rocks. Some high-level granitesof the Makkovik Province, although best known fortheir molybdenum mineralization, are locally associ-ated with marginal galena–sphalerite veins (e.g., BigBight prospect) developed within volcanic countryrocks (Figure 5).

Clastic Sediment-HostedMineralization Environments

Finally, there are a number of zinc and lead occur-rences associated with sandstone–shale se-

quences. Neoproterozoic clastic rocks of the easternAvalon Zone near Carbonear (Figure 2) host wide-spread low-grade Pb–Zn mineralization of SEDEXstyle associated with surface gossans. In Labrador(Figure 5), the Paleoproterozoic clastic rocks of theMoran Lake Group (Teuva occurrence, northern

7

The major source ofproduction from volcanic-hosted

environments has been the Buchansdeposits, where five major orebodieswere mined between 1928 and 1984

for a total of 16.2 million tonnesat average grades of 14.51% zinc,

7.56% lead, 1.33% copper, 1.37 g/tgold and 126.0 g/t silver. In terms of

the value of the metal produced,these rank as world-class deposits

and underscore the potential ofthe central Newfoundland

volcanic terranes.

Makkovik Province) also locally host small strata-bound zinc occurrences in association with pyriticgossans. The coeval shales of the western LabradorTrough contain elevated zinc levels in lake sedimentsbut in situ mineralization has yet to be discovered.

Exploration Potential

The carbonate-hosted mineralization environmentsof western Newfoundland have seen relatively lit-

tle exploration since the closure of the Daniel’sHarbour mine, but it is anticipated that activity willresume as the price of zinc rebounds from the lows ofthe late 1990s. The most favourable area for explo-ration is probably north of Bonne Bay (Figure 2)where the requisite secondary dolomitization andpseudobreccia are most abundant.

The search for volcanic-hosted polymetallicdeposits of the Buchans type has always been a main-stay of exploration in Newfoundland and will doubt-less continue in all areas of the highly prospectiveDunnage Zone. For a considerable time the most pros-pective parts of this area were held under long-termconcession by a limited number of companies.However, these holdings have now been broken upinto a number of smaller parcels resulting in a resur-gence of junior company interest in the area.

The clastic-hosted, or SEDEX, environment isarguably the least-explored lead–zinc environment inthe Province. Paleoproterozoic clastic sequences inLabrador, notably the Labrador Trough and theRamah, Mugford and Moran Lake groups, may havesignificant grassroots potential in this respect.

Selected BibliographyCarbonate-Hosted Environments

Crossley, R.V. and Lane, T.1984: A guide to the Newfoundland Zinc Mines Limitedore bodies, Daniel’s Harbour. In Mineral Deposits ofNewfoundland - A 1984 Perspective. NewfoundlandDepartment of Mines and Energy, Mineral DevelopmentDivision, Report 84-3, pages 45-51.

Knight, I.1984: Mineralization in Cambro-Ordovician rocks, west-ern Newfoundland. In Mineral Deposits of Newfoundland- A 1984 Perspective. Newfoundland Department ofMines and Energy, Mineral Development Division,Report 84-3, pages 37-44.

Lane, T.E.1984. Preliminary classification of carbonate breccias,Newfoundland Zinc Mines, Daniel’s Harbour, New-

foundland. In Newfoundland Department of Mines andEnergy, Mineral Development Division, Report 84-1,pages 131-140.

Saunders, C.M., Strong, D.F. and Sangster, D.F.1992: Carbonate-hosted lead-zinc deposits of westernNewfoundland. Geological Survey of Canada, Bulletin419, 78 pages.

Wilton, D.H.C., Archibald, S.M., Hussey, A.M. and Butler,R.W. Jr.

1994: Metallogeny of the Ramah Group: discovery of anew Pb–Zn exploration target, northern Labrador. InCurrent Research. Newfoundland Department of Minesand Energy, Geological Survey, Report 94-1, pages 415-428.

Volcanic-Hosted Environments

Sears, W.A. and O’Driscoll, C.F.1989: Metallogeny of the Connaigre Bay Group, southernNewfoundland. In Current Research. Department ofMines, Geological Survey of Newfoundland, Report 89-1,pages 193-199.

Swinden, H.S., Evans, D.T.W. and Kean, B.F.1991: Metallogenic framework of base and precious metaldeposits, central and western Newfoundland (Field Trip1), 8th. IAGOD Symposium Field Trip Guidebook.Geological Survey of Canada, Open File 2156, 232 pages.

Thurlow, J.G.1981: The Buchans Group: its structural and stratigraphicsetting, In The Buchans Orebodies: 50 Years of Geologyand Mining. Edited by E.A. Swanson, D.F. Strong and J.G.Thurlow. Geological Association of Canada, SpecialPaper 22, pages 79-90.

Thurlow, J.G. and Swanson, E.A.1987: Stratigraphy and structure of the Buchans Group. InBuchans Geology, Newfoundland. Edited by R.V.Kirkham. Geological Survey of Canada, Paper 86-24,pages 35-46.

Other Environments

Evans, D.T.W.1996: Epigenetic gold occurrences, eastern and centralDunnage Zone, Newfoundland. Geological Survey,Mineral Resource Report 9, 135 pages.

Wilton, D.H.C.1996: Metallogeny of the Central Mineral Belt and adja-cent Archean basement, Labrador. NewfoundlandDepartment of Mines and Energy, Geological Survey,Mineral Resource Report 8, 178 pages.

General Information

Martin, W.1983: Once Upon a Mine: Story of the Pre-ConfederationMines on the Island of Newfoundland. Canadian Instituteof Mining and Metallurgy, Special Volume 26, 98 pages.

8


Documents

MINERAL COMMODITIES OF NEWFOUNDLAND AND …Mineral Commodities of Newfoundland and Labrador Zinc and Lead Foreword This is the first in a series of summary publications covering the