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How a diamond is formed
Transcript of How a diamond is formed
How a diamond is formed
Diamonds are formed at deep pressure and brought to the surface with a large volcanic eruption.Popular to contrary belief,coal does not or even rarely play a role in the formation of a diamond.Diamonds have formed way before plants have even fossilized into coal.Apparently,there are 4 processes that geologists think are responsible for the formation of diamonds.Those 4 processes are: deep source eruptions, subduction zone diamonds, asteroid impact diamonds and
diamonds formed in space.The formation
process requires high temperatures and high
pressure where temperatures can reach up to 2000
degrees Celsius.These temperature rates and pressure
types are not present globally.
How synthetic diamonds are formed
Synthetic diamonds are made by first weakening graphite,which also contains carbon.After the graphite is weakened,it is exposed to extreme temperatures and pressures.This process was developed by the scientists Robert Wentorf, Tracy Hall, Francis Bundy and Herbert Strong.This secret of forming synthetic diamonds was unlocked in the 1950s.More than 100 tons of synthetic diamonds are made anually and almost all are used for industry.
One famous diamond was the Hope Diamond, which was the largest deep blue diamond in the world.This gem was donated by the jeweler Harry Winston to the Smithsonian Institution in 1958.It was surrounded by 16 pear shaped, cushion cut diamonds and hanged from a chain of 45 diamonds.
Another one is the Star of Africa.It is shaped like a pear and it weighs 530.20 carats.The Star of Africa measures 58.9 x 45.4 x 27.7 mm.It holds the place of the 2nd largest cut diamond in the world.It also is called Cullinan I because it is the largest of all the 9 stones cut from the
1. Deep source eruptions
Geologists think that all of Earth's commercial deposits of diamonds were formed in the mantle and delivered to the surface by volcanic eruptions deep down.These types of eruptions produce the kimberlite and lamproite pipes sought after by diamond prospectors.Diamonds that are eroded and weathered away from these pipes by water or wind are now found in the sedimentary layers of streams and coastlines.Coal in fact,is not involved in this process.Coal is a sedimentary rock and it is rarely buried to depths past 3.2 km (2 miles).The source of carbon for these diamonds is most likely carbon trapped in the Earth's interior.
2.Diamond formation in subduction zones
Small diamonds are trapped in rocks that are thought to have been subducted deep into the mantle by tectonic plate processes and then returned to the surface.Diamonds forming in a subducting plate might occur as little as 80 km (50 miles) below the surface and at temperatures as low as 200 degrees Celsius (390 degrees Fahrenheit.Coal is a possible carbon source for this process but the most likely sources are carbonate rocks such as limestone,dolomite,marble and possibly particles of plant debris.
3.Asteroid impact zone diamonds
Throughout Earth's history, it has been repeatedly been hit by large asteroids.When such asteroid types strike Earth, extreme temperatures and pressures are generated.For example,when an asteroid 10 kilometers and traveling at 15 to 20 kilometers per second strikes Earth, this hypervelocity object would generate an energy burst equivalent to millions of nuclear weapons and temperatures hotter than the Sun's surface.The extreme temperatures and conditions are more than adequate for diamonds to form.This theory of the formation of diamonds is supported by the dicovery of sub-millimeter sized diamonds around several asteroid impact sites.Is coal involved in this process? Coal could be present in the impact area and could serve as the carbon source.Other carbon bearing rocks such as limestone dolomites and marlbes could also be present in the area and serving as the carbon source.
4.Diamond formation in space
Researchers from NASA have detected large numbers of nanodiamonds(diamonds that are a few nanometers in diameter.Nanometers are billionths of a meter) in some meteorites.Around 3% of carbon detected in these meteorites are in the form of nanodiamonds.These types of diamonds are too small to be used as gemstones or industrial abrasive material.However, they are a source of diamond material.Is coal involved? Coal is not involved in this process.The carbon source for this formation process for diamonds would be a body other than Earth.
Star of Africa