GIA Diamond Formation, Mining, and the Diamond Market 1 — Questions and Answers
Question 1: Where do most natural diamonds form?
- In volcanoes
- In sedimentary basins
- In the Earth’s mantle (Correct answer)
- In riverbeds
Correct answer: In the Earth’s mantle
Natural diamonds form deep within the Earth's mantle, approximately 90 to 120 miles (140 to 190 kilometers) below the surface. This process requires extreme conditions of high temperature (over 2,000°F or 1,100°C) and immense pressure, which cause carbon atoms to crystallize into the diamond structure. These diamonds are then brought closer to the surface through deep volcanic eruptions.
Question 2: What is kimberlite?
- A diamond cutting tool
- A synthetic material
- Volcanic rock bearing diamonds (Correct answer)
- An artificial simulant
Correct answer: Volcanic rock bearing diamonds
Kimberlite is a type of igneous rock that originates deep within the Earth's mantle and is the primary host rock for diamonds. It forms through explosive volcanic eruptions that bring diamonds from the mantle to the Earth's surface in pipe-like formations. These kimberlite pipes are the most significant source of primary diamond deposits worldwide.
Question 3: Which country is one of the largest producers of diamonds by volume?
- India
- United States
- Russia (Correct answer)
- Brazil
Correct answer: Russia
Russia is consistently one of the world's largest producers of natural diamonds by volume, with extensive mining operations primarily in the Siberian region. Companies like ALROSA contribute a substantial portion of the global rough diamond supply. Its vast diamond reserves and advanced mining infrastructure make it a dominant player in the international diamond market.
Question 4: What role does the De Beers Group play in the diamond industry?
- Regulates global prices
- Sells only synthetic stones
- Dominated global supply and marketing (Correct answer)
- Operates all retail outlets
Correct answer: Dominated global supply and marketing
For much of the 20th century, the De Beers Group held a near-monopoly on the global diamond supply, controlling a vast majority of rough diamond production and distribution. Through strategic marketing campaigns, such as 'A Diamond Is Forever,' they also significantly influenced consumer demand and perceptions of diamonds. While their market share has decreased, their historical dominance shaped the modern diamond industry.
Question 5: What is alluvial diamond mining?
- Mining from volcanic rock
- Open-pit blasting
- Extracting from waterways and sediments (Correct answer)
- Subsurface drilling
Correct answer: Extracting from waterways and sediments
Alluvial diamond mining involves recovering diamonds that have been eroded from their primary source (like kimberlite pipes) and transported by natural forces, such as rivers, streams, and ocean currents. These diamonds accumulate in secondary deposits like riverbeds, beaches, and ancient floodplains. Miners typically use methods like panning, dredging, or sifting to extract diamonds from these loose sediments.
Question 6: What does the Kimberley Process aim to prevent?
- Over-mining
- Fake gemstone marketing
- Illegal gold trading
- Trade in conflict diamonds (Correct answer)
Correct answer: Trade in conflict diamonds
The Kimberley Process Certification Scheme (KPCS) is an international initiative established to prevent the flow of 'conflict diamonds' (also known as 'blood diamonds') into the legitimate global market. Conflict diamonds are rough diamonds used by rebel movements to finance wars against legitimate governments. The KPCS requires participating countries to certify that their rough diamonds are conflict-free, aiming to ensure ethical sourcing.
GIA Diamond Formation, Mining, and the Diamond Market 1
Where do most natural diamonds form?