Chapter 4 Major Diamond-Producing Areas Flashcards
What you can say about landmasses in the long earth’s history?
Landmasses have moved constantly in the earth’s history.
What place was earth 230 million years ago?
A different place, continents were joined in a supercontinent.
How scientists called supercontinent that was 230 million years ago on earth?
Pangea
How much of surface of planet was covered by Pangea continent?
Half of the planet, rest was ocean.
What happened 80 million years after Pangea was created?
Pangea has separated into two landmasses: Laurasia and Gondwana.
What happened later with Laurasia and Gondwana?
The two landmasses continued to move apart.
What happened to Gondwana?
Gondwana broke into what became South America, Africa, India, Australia, and Antarctica.
What happened to Laurasia?
Laurasia became North America, Europe and Asia (except India).
What geologists find out by comparing North and South Americas to the continents across the Atlantic Ocean?
They discovered similar kinds of rocks and geologic structures.
What ancient landmasses connections means to diamond explorers?
This means that for example Africa’s diamond fields were once connected to the diamond fields in Brazil, and in the north, recent Canadian diamond finds are mirrored in northern Russia.
Where are most important diamond-producing areas found?
Africa, Australia, Eurasia, and North and South America.
Where are historic viable sources were first discovered?
India, Brazil, and in South Africa.
Which countries are the largest producer by value in $ and by volume?
Russia, Botswana, and Canada.
Who has been the most important diamond-producing area for nearly a century and half since late 1800’s.
Africa
Which area has world’s most diverse diamond sources, and why?
Africa due to its wide range of geological and geographical feature.
Which country in Africa is one of the top three diamond-producing countries by value and volume?
Botswana.
Which mine is the oldest one of Debswana operations?
Orapa
When Orapa began its operation?
In 1971.
Which mine and where is the world’s richest diamond mine in term of value?
Jwaneng, Botswana
From which mines De Beers sources the majority of its diamonds?
From Orapa and Jwaneng mines in Botswana.
Where are clustered diamond deposits in Africa?
Diamond deposits are clustered in Southern Africa, Central Africa, and the west coast of Africa.
Name mine located in Angola?
Catoca mine
Name mine located in Namibia?
De Beers Marine, Elizabeth Bay
Name mines located in Botswana?
Orapa, Letlhakane, Jwaneng
Name mines located in South Africa?
Venetia, Cullinan, Finsch
What is famous for Cullinan mine?
It’s famous for its blue diamonds, the world’s largest rough diamond, and many important stones in British Crown Jewels.
What is Letseng mine known for in Lesotho?
Its famous for consistent production of large diamonds.
Name mines located in Lesotho?
Letseng mine.
What kind of mines are found in Zimbabwe?
The country has both open-pit mines and alluvial diamond deposits.
Name open pit mines in Zimbabwe?
RZM Murowa
Who is operating in alluvial deposits in Zimbabwe?
It’s worked by local miners with simple tools.
Which mine in Angola is most productive?
Catoca mine.
Which countries in Africa are also diamond producers?
Sierra Leone, Guinea, Ghana, and Ivory Coast.
Which country is marine diamond leading producer?
Namibia, nearly 70% of country’s production is recovered from the Atlantic Ocean.
What kinds deposits are mostly found in Central African Republic and Democratic Republic of Congo?
Alluvial deposits.
Which mine in Australia was the most economically important?
Argyle mine
Name mines in Australia?
Argyle (closed in 2020), Ellendale and Merlin
Who was running Argyle mine?
Rio Tinto
When Argyle mine began production?
In 1983?
What kind of mining was made in Argyle mine?
Open-pit and underground mining operations.
Do Lomonosov and Argyle mine are located on craton?
No, and it contradicted Clifford’s Rule.
What caused Argyle’s mine closure to Australia’s diamond production?
Australia’s diamond production to drop by 99 precent.
What for Ellendale mine famous for?
It once produced more than half of the world’s yellow diamonds.
When Ellendale mine was developed?
In 1976
Is Merlin mine is lamproite?
No it’s a kimberlite pipe and located in Northern Territory.
When Argyle mine was converted to an underground mine?
In 2006
What was the average size of rough from Argyle?
About 0.1 ct
To which landmass was once connected the Americas landmass?
To Africa and Eurasia
Which of Americas hosts some of the best diamond sources?
North America.
Which country is considered one of the top 3 largest diamond-producing countries in terms of both value and volume?
Canada
When and where in Canada two geologists found diamond-bearing kimberlite pipes?
In 1991, about 300 km north of Yellowknife, Northwest Territories.
How was named first mine pipe in Canada?
Ekati
Which mine in Canada began to produce diamonds in 2003?
Diavik
Which mines in Canada began production in 2017?
Renard and Gancho Kué.
Where are located Canadian diamond mines?
They are located in remote areas, in extreme operating conditions.
For what technical features are Canadian mines are known?
The are known for engineering feats, such as Ekati’s lake-bottom open-pit mine and ice road that must be built annually to supply mines in winter months.
What is largest yellow diamond found to date 2018 in North America?
The 552,7 ct yellow diamond.
Is some portions of US lie atop cratons?
Yes
Is geoleogy of US is considered favorable for diamond deposition?
No
When and by whom in 1906 diamond was found in US?
By John Huddleston on his farm near Murfreesboro, Arkansas.
How many pipes were found on Huddleston’s farm in Arkansas?
4, two of which have produced diamonds. But mainly industrial grade diamonds, and low profit.
How is called attraction for amateur prospectors in Arkansas?
Crater of Diamonds State PArk in Arkansas.
Can you tell best finds in Crater of Diamonds in Arkansas?
6.19 ct in 2014, 8.52ct white diamond in 2015, 7.66 ct brown diamond in 2017, and 6.39 ct white diamond in 2020
Where are concentrated main operations in Brazil?
In Mato Grosso and Minas Geiras states.
What are most types of deposits are found in Brazil?
Alluvial deposits.
Where are coming earliest reported superdeep diamonds from?
Brazil.
What type of diamond is sourced mainly from Brazil?
Carbonado.
Which countries are source of diamonds in South America?
Brazil, Venezuela and Guyana.
How much and what kind of deposits are mined in Russia?
11 kimberlite pipes and 16 alluvial deposits
Name most famous Russian diamond mines?
Mir, Jubilee and Udachny.
When Mir mine began operation in Siberia?
In 1957, currently it’s closed, while research is undertaken on how to expand it’s production.
When ALROSA opened Jubilee mine?
In 1989 and is currently one of the top producing mines.
When Udachny open-pit mining began?
In 1971 and ended in 2015. It’s underground mine is still under construction.
What is newest ALROSA diamond operation?
Lomonosov, located in north-western part of the country. Production began in the early 2000s /20 years after discovery od diamonds deposit/
What diamonds are found in Lomonosov?
Pink, yellow, green, and brown diamonds.
“Does the Lomonosov mine comply with Clifford’s Rule?”
No, because deposit is not found on craton but in much younger suite of host rocks, contradicting CR.
How much of Lomonosov’s mine production consists of fancy colored diamonds??
0,04 precent.
After whom Lomonosov mine is named?
After Mikhail Lomonosov, one of the founders of Moscow State University.
Where is Lomonosov deposit located?
Deposit is located within the Baltic Shield, part of east European Craton. This is Europe’s first diamond deposit.
How many kimberlites are present in Baltic Shield?
There are 10 kimberlite deposits.
How many kimberlite deposits in Baltic Shield contain diamonds in profitable quantities?
6
Which fancy color diamonds are found in Lomonosov deposit?
Pink, purple, violet, green, yellow, and brown.
Where are sold fancy color diamonds from Lomonosov Deposit?
In New York, Tel Aviw, Dubai, Antwerp, Hong Kong, and Moscow.
How are sold fancy color diamonds from Lomonosov Deposit?
At auctions with blind bids.
