The Pine Point Mine is located on the south shore of
Great Slave Lake
Great Slave Lake (french: Grand lac des Esclaves), known traditionally as Tıdeè in Tłı̨chǫ Yatıì (Dogrib), Tinde’e in Wıìlıìdeh Yatii / Tetsǫ́t’ıné Yatıé (Dogrib / Chipewyan), Tu Nedhé in Dëne Sųłıné Yatıé (Chi ...
between
Hay River to the west and
Fort Resolution
Fort Resolution (''Denı́nu Kų́ę́'' (pronounced "deh-nih-noo-kwenh") "moose island place") is a hamlet in the South Slave Region of the Northwest Territories, Canada. The community is situated at the mouth of the Slave River, on the shores o ...
to the east, in the
Northwest Territories
The Northwest Territories (abbreviated ''NT'' or ''NWT''; french: Territoires du Nord-Ouest, formerly ''North-Western Territory'' and ''North-West Territories'' and namely shortened as ''Northwest Territory'') is a federal territory of Canada. ...
of
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
. It produced
lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...
and
zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...
ore
Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 April 2 ...
s from a
Mississippi Valley Type deposit between 1964 and 1988. Most of the mining was done by
open-pit methods. The town of
Pine Point was built by the mining company,
Cominco
Teck Resources Limited, known as Teck Cominco until late 2008, is a diversified natural resources company headquartered in Vancouver, British Columbia, that is engaged in mining and mineral development, including coal for the steelmaking indust ...
, and when the mine closed the town was abandoned and demolished.
History
The Pine Point ore deposit was discovered in the late 19th century by fur traders at Fort Resolution who learned of the lead ores from the natives. A minor staking rush occurred in 1898 when
Klondike prospectors heard rumours of
silver
Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, whi ...
at the location. There was no silver to be found, and although the lead ore was very rich, it was not feasible to mine the isolated deposit without good transportation to the south.
The first major exploration work was done in 1928–1930 when several short
shafts were sunk and a
churn drill
The churn drill is a large drilling machine that bores large diameter holes in the ground. In mining, they were used to drill into the soft carbonate rocks of lead and zinc hosted regions to extract bulk samples of the ore. Churn drills are also ca ...
was brought to the area to drill into the rich ores. That work was halted by the
Great Depression
The Great Depression (19291939) was an economic shock that impacted most countries across the world. It was a period of economic depression that became evident after a major fall in stock prices in the United States. The economic contagio ...
. Geological investigation by
Cominco
Teck Resources Limited, known as Teck Cominco until late 2008, is a diversified natural resources company headquartered in Vancouver, British Columbia, that is engaged in mining and mineral development, including coal for the steelmaking indust ...
after
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
led to new theories of how the ore deposits were hosted, and by 1955 an extensive exploration program had outlined several thousand tons of ore along a belt.
The
Government of Canada
The government of Canada (french: gouvernement du Canada) is the body responsible for the federal administration of Canada. A constitutional monarchy, the Crown is the corporation sole, assuming distinct roles: the executive, as the ''Crown ...
built the
Great Slave Railway
Great may refer to: Descriptions or measurements
* Great, a relative measurement in physical space, see Size
* Greatness, being divine, majestic, superior, majestic, or transcendent
People
* List of people known as "the Great"
*Artel Great (born ...
from
Grimshaw, Alberta
Grimshaw is a town in northern Alberta, Canada. It is approximately west of the Town of Peace River at the junction of Highway 2 and Highway 2A and along Mackenzie Northern Railway. By virtue of being the original starting point of Highway ...
to the mine; construction started in 1962 and was completed in 1964, at which time it was made part of the then-Crown Corporation
CN Rail
The Canadian National Railway Company (french: Compagnie des chemins de fer nationaux du Canada) is a Canadian Class I railroad, Class I freight railway headquartered in Montreal, Quebec, which serves Canada and the Midwestern United States, M ...
. The railway line was sold by CN Rail to become a short line named the
Mackenzie Northern Railway
The Mackenzie Northern Railway is a Canadian railway operating in Alberta and the Northwest Territories. It is the northernmost trackage of the contiguous North American railway network. Since being purchased by CN in 2006, it has been official ...
, but was later reacquired by CN Rail.
Official production at the mine commenced in 1965. Cominco built its own townsite which became known as Pine Point. It became a territorial settlement with private businesses, and boasted a population of nearly 2,000 at its peak. When the mine closed in 1988, the single-industry town was forced to close, and the rail spur was removed.
The mine produced and shipped 10,785,000 tons of lead and zinc
concentrate
A concentrate is a form of Chemical substance, substance that has had the majority of its base component (in the case of a liquid: the solvent) removed. Typically, this will be the removal of water from a Solution (chemistry), solution or suspens ...
s/high-grade ores after mining and milling 69,416,000 tons of ore material. Contained metal was approximately 2 million tons of lead and 7 million tons of zinc.
Development since 2000
In the 2000s, Tamerlane Ventures Inc. purchased the mine in the hopes of restarting the operations. The effort failed due to low metal prices at the time and the company filed for bankruptcy.
Darnley Bay Resources Ltd. purchased the project for $8 million in December 2016 and hired about 20 staff in neighbouring communities for exploratory drilling and line cutting.
The company is expected to invest $154 million into the mine and would employ 320 workers at full capacity. The company highlighted cost savings from the nearby highway and railroad constructed previously for the mine in 1980s as well as the electricity generated from the hydroelectric project from
Taltson River
The Taltson River is a roughly river in the Northwest Territories of Canada that drains into the Great Slave Lake.
There are three hydroelectric power control structures on the river, and one power station.
Name
The river was formerly known as t ...
.
Geology
The Pine Point deposit is a
carbonate hosted lead-zinc ore deposit (Mississippi Valley Type deposit). It consists of a series of more than 80 bodies of lead-zinc
mineralization distributed along a trend about long by about wide.
[Qing, H. 1998. Petrography of early-stage, fine- and medium-crystalline dolomites in the Middle Devonian Presqu'ile Barrier at Pine Point, Canada. Sedimentology vol. 45, no. 2, p. 433-446.] The ore is localized in solution-collapse (
karst
Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...
) structures where
sulfide minerals
The sulfide minerals are a class of minerals containing sulfide (S2−) or disulfide (S22−) as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenides, the tellurides, the ...
preferentially replaced some of the
carbonate host rocks,
dolomite Dolomite may refer to:
*Dolomite (mineral), a carbonate mineral
*Dolomite (rock), also known as dolostone, a sedimentary carbonate rock
*Dolomite, Alabama, United States, an unincorporated community
*Dolomite, California, United States, an unincor ...
and
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
), of the
Presqu'ile Formation. Minerals present include
galena
Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver.
Galena is one of the most abundant and widely distributed sulfide minerals. It cryst ...
,
sphalerite
Sphalerite (sometimes spelled sphaelerite) is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in Sedimentary exhalative deposits, sedimen ...
,
marcasite
The mineral marcasite, sometimes called “white iron pyrite”, is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both ...
,
pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrite's metallic Luster (mineralogy), lust ...
,
dolomite Dolomite may refer to:
*Dolomite (mineral), a carbonate mineral
*Dolomite (rock), also known as dolostone, a sedimentary carbonate rock
*Dolomite, Alabama, United States, an unincorporated community
*Dolomite, California, United States, an unincor ...
,
calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...
,
sulphur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...
and
bitumen
Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term a ...
. The sulfide minerals were probably deposited by
hydrothermal fluids that rose along an underlying
shear zone
In geology, a shear zone is a thin zone within the Earth's crust or upper mantle that has been strongly deformed, due to the walls of rock on either side of the zone slipping past each other. In the upper crust, where rock is brittle, the shear ...
.
[Gleeson, S.A. and Turner, W.A. 2007. Fluid inclusion constraints on the origin of the brines responsible for Pb–Zn mineralization at Pine Point and coarse non-saddle and saddle dolomite formation in southern Northwest Territories. Geofluids v. 7, no. 1, p. 51-68.]
References
* Bérubé, Y. (1972). ''An Engineering asse
ment of waste water handling procedures, at the Cominco Pine Point mine final report''. Laval, Quebec: Centre de recherches sur l'eau, Universite Laval.
* Deprez, P. (1973). ''The Pine Point Mine and the development of the area south of Great Slave Lake''. Winnipeg: Center for Settlement Studies, University of Manitoba.
* Evans, M. S., Klaverkamp, J. F., & Lockhart, L. (1998). ''Metal studies of water, sediments and fish from the Resolution Bay area of Great Slave Lake studies related to the decommissioned Pine Point Mine''. Saskatoon, Sask: National Hydrology Research Institute.
* Norris, A. W., & Uyeno, T. T. (1998). ''Middle Devonian brachiopods, conodonts, stratigraphy, and transgressive-regressive cycles, Pine Point area, south of Great Slave Lake, District of Mackenzie, Northwest Territories''. Ottawa: Natural Resources Canada.
* Pine Point Mines Limited. (1978). ''Zinc/lead mining at Pine Point, N.W.T''. Pine Point, N.W.T.: The Mines.
* Wilson, J., & Petruk, W. (1985). ''Quantitative mineralogy of Pine Point tailings''.
ttawa? CANMET, Energy, Mines and Resources Canada.
External links
{{Commons category, Pine Point mine, NWT, Pine Point Mine
A web documentary about the town of Pine Point was produced in 2011 by the National Film Board of Canada and The Goggle
1926 Ted Nagle and the Pine Point DiscoveryNWT Historical Timeline, Prince of Wales Northern Heritage Centre
* Former residents of Pine Point have built a website to house photos of the tow
Former mines in Canada
Lead mines in Canada
Mines in the Northwest Territories
Open-pit mines
Underground mines in Canada
Zinc mines in Canada