Murowa diamond mine
Encyclopedia
The Murowa diamond mine is a diamond
mine
located in Mazvihwa, south central Zimbabwe
, about 40 kilometres from the asbestos mining town of Zvishavane in the Midlands province. The mine is majority owned and operated by the Rio Tinto Group
, which also owns the Argyle diamond mine
in Australia
and part of the Diavik Diamond Mine
in Canada
. The mine is a combination of open pit and underground construction; current estimates put construction costs at $61 million USD and mine reserves are 19 million tonne
s of ore
, with an ore grade of 0.9 carats (180 mg) per tonne
pipes, intrusive into the Chivi suite granite
s of the Zimbabwe Craton
. The kimberlites have been dated at 500 Ma.
pipes
were discovered; over a period of three years of study, the two larger pipes have been determined to be economically feasible as mines. Construction of mine facilities was completed in late 2004. Preparation for mining included the forced relocation of 926 people living on the mine site to six farms purchased by a government relocation program. Limited mining operations began in Murowa in 2004, with full capacity expected to be reached sometime in 2005, although permitting problems have slowed progress toward this milestone. Full scale production is expected to process 200,000 tonnes of ore annually, although it is possible to push production to as much as one million tonnes annually through further capital investment.
The mine is a combination of open pit and underground construction; current estimates put construction costs at $61 million USD. Current estimates of mine reserves are 19 million tonne
s of ore
, with an ore grade of 0.9 carats (180 mg) per tonne. Rio Tinto estimates that over the life of the mine, prices for the Murowa's production will fetch an average price of $65 USD per carat (325 $/g).
Diamond
In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions...
mine
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
located in Mazvihwa, south central Zimbabwe
Zimbabwe
Zimbabwe is a landlocked country located in the southern part of the African continent, between the Zambezi and Limpopo rivers. It is bordered by South Africa to the south, Botswana to the southwest, Zambia and a tip of Namibia to the northwest and Mozambique to the east. Zimbabwe has three...
, about 40 kilometres from the asbestos mining town of Zvishavane in the Midlands province. The mine is majority owned and operated by the Rio Tinto Group
Rio Tinto Group
The Rio Tinto Group is a diversified, British-Australian, multinational mining and resources group with headquarters in London and Melbourne. The company was founded in 1873, when a multinational consortium of investors purchased a mine complex on the Rio Tinto river, in Huelva, Spain from the...
, which also owns the Argyle diamond mine
Argyle diamond mine
The Argyle Diamond Mine is a diamond mine located in the East Kimberley region in the remote north of Western Australia. Argyle is the largest diamond producer in the world by volume, although due to the low proportion of gem-quality diamonds, is not the leader by value. It is the only known...
in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and part of the Diavik Diamond Mine
Diavik Diamond Mine
The Diavik Diamond Mine is a diamond mine in the North Slave Region of the Northwest Territories, Canada, about north of Yellowknife.It has become an important part of the regional economy, employing 700, grossing C$100 million in sales, and producing 8 million carats of diamonds annually...
in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. The mine is a combination of open pit and underground construction; current estimates put construction costs at $61 million USD and mine reserves are 19 million tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s of ore
Ore
An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element....
, with an ore grade of 0.9 carats (180 mg) per tonne
Geology of the Deposit
Murowa consists of three north-trending kimberliteKimberlite
Kimberlite is a type of potassic volcanic rock best known for sometimes containing diamonds. It is named after the town of Kimberley in South Africa, where the discovery of an diamond in 1871 spawned a diamond rush, eventually creating the Big Hole....
pipes, intrusive into the Chivi suite granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
s of the Zimbabwe Craton
Zimbabwe craton
The Zimbabwe craton is an area in Southern Africa of ancient continental crust and an example of Early Archaean lithology dating back to 3.5 billion years ago in the southern African nation of Zimbabwe. Late Archean metamorphism joined the Southern Marginal Zone of the Kaapvaal craton to the...
. The kimberlites have been dated at 500 Ma.
History
The Murowa site's possibilities were first realized in 1997, when three diamond-bearing kimberliteKimberlite
Kimberlite is a type of potassic volcanic rock best known for sometimes containing diamonds. It is named after the town of Kimberley in South Africa, where the discovery of an diamond in 1871 spawned a diamond rush, eventually creating the Big Hole....
pipes
Volcanic pipe
Volcanic pipes are subterranean geological structures formed by the violent, supersonic eruption of deep-origin volcanoes. They are considered to be a type of diatreme. Volcanic pipes are composed of a deep, narrow cone of solidified magma , and are usually largely composed of one of two...
were discovered; over a period of three years of study, the two larger pipes have been determined to be economically feasible as mines. Construction of mine facilities was completed in late 2004. Preparation for mining included the forced relocation of 926 people living on the mine site to six farms purchased by a government relocation program. Limited mining operations began in Murowa in 2004, with full capacity expected to be reached sometime in 2005, although permitting problems have slowed progress toward this milestone. Full scale production is expected to process 200,000 tonnes of ore annually, although it is possible to push production to as much as one million tonnes annually through further capital investment.
The mine is a combination of open pit and underground construction; current estimates put construction costs at $61 million USD. Current estimates of mine reserves are 19 million tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s of ore
Ore
An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element....
, with an ore grade of 0.9 carats (180 mg) per tonne. Rio Tinto estimates that over the life of the mine, prices for the Murowa's production will fetch an average price of $65 USD per carat (325 $/g).