Coal has rarely played a role in the formation of diamonds. In fact, most diamonds that have been dated are much older than Earth's first land plants - the source materials of coal! That alone should be enough evidence to shut down the idea that Earth's diamonds deposits were formed from coal.
Another problem with the idea is that coal seams are sedimentary rocks that usually occur as horizontal rock units. However, the source rocks of diamonds are vertical pipes filled with igneous rocks.
Four processes are thought to be responsible for virtually all of the natural diamonds that have been found at or near Earth's surface. One of these processes accounts for nearly 100% of all diamonds that have ever been mined. The remaining three are insignificant sources of commercial diamonds.
These process rarely involve coal
1) Diamonds formation in Earth's Mantle.
Geologist believe that the diamonds in all of Earths commercial diamond deposits were formed in the mantle and delivered to the surface by deep-source volcanic eruptions. The formation of natural diamonds requires very high temperatures and pressures. This conditions occur in limited zones of Earth's mantle about 90 miles (150 kilometers) below the surface where temperatures are at least 2000 degrees Fahrenheit (1050 degrees Celsius).
2) Diamond formation at impact zones:
Tiny diamonds have been found in rocks that are thought to have been subducted deep into the mantle by plate tectonic process- then returned to the surface. Diamond formation in a subducting plate might occur as little as 50 miles (80 kilometers) below the surface and at temperatures as low as 390 degrees Fahrenheit (200 degrees Centigrade). In another study, diamonds from Brazil were found to contain tiny mineral inclusions consistent with mineralogy of oceanic crust.
Is coal involved? Coal is a sedimentary rock, formed from plant debris deposited at Earth's surface. It is rarely buried to depths greater than two miles (3.2 kilometers). It is very unlikely that coal has been moved from the crust down to a depth well below the base of a continental plate. The carbon source for these mantle diamonds is most likely carbon trapped in Earth's interior at the time of the planet's formation.
3) Diamond Formation at Impact Sites
Throughout its history, Earth has been repeatedly hit by large asteroids. When these asteroids strike the earth extreme temperatures and pressures are produced. For example: when a six mile (10 kilometer) wide asteroid strikes the earth, it can be traveling at up to 9 to 12 miles per second (15 to 20 kilometers per second). Upon impact this hypervelocity object would produce an energy burst equivalent to millions of nuclear weapons and temperatures hotter than the sun's surface (5).
The high temperature and pressure conditions of such an impact are more than adequate to form diamonds. This theory of diamond formation has been supported by the discovery of tiny diamonds around several asteroid impact sites. See Location 3 in the diagrams above and at right.
Tiny, sub-millimeter diamonds have been found at Meteor Crater in Arizona. Polycrystalline industrial diamonds up to 13 millimeters in size have been mined at the Popigai Crater in northern Siberia, Russia.
Is coal involved? Coal could be present in the target area of these impacts and could serve as the carbon source of the diamonds. Limestones, marbles, dolomites and other carbon-bearing rocks are also potential carbon sources.
4) Formation in Space
NASA researchers have detected large numbers of nanodiamonds in some meteorites (nanodiamonds are diamonds that are a few nanometers - billionths of a meter in diameter). About three percent of the carbon in these meteorites is contained in the form of nanodiamonds. These diamonds are too small for use as gems or industrial abrasives, however, they are a source of diamond material (6), See Location 4 in the diagrams above and at right.
Smithsonian researchers also found large numbers of tiny diamonds when they were cutting a sample from the Allen Hills meteorite (7). These diamonds in meteorites are thought to have formed in space through high speed collisions similar to how diamonds form on Earth at impact sites.
Is coal involved? Coal is not involved in the creation of these diamonds. The carbon source is from a body other than Earth.
The most convincing evidence that coal did not play a role in the formation of most diamonds is a comparison between the age of Earth's diamonds and the age of the earliest land plants.
Almost every diamond that has been dated formed during the Precambrian Eon - the span of time between Earth's formation (about 4,600 million years ago) and the start of the Cambrian Period (about 542 million years ago). In contrast, the earliest land plants did not appear on Earth until about 450 million years ago - nearly 100 million years after the formation of virtually all of Earth's natural diamonds.
Since coal is formed from terrestrial plant debris and the oldest land plants are younger than almost every diamond that has ever been dated, it is easy to conclude that coal did not play a significant role in the formation of Earth's diamonds.
Well, that's it on these diamond, and what do you think about this:
According to CBS News:
It may sound a bit dark, but it’s now possible to transform the ashes of the cremated deceased into a diamond–a jewel truly to remember.
Using “Russian technology,” Algordanza Memorial Diamonds are created in a similar fashion to the way natural diamonds are formed.
Here’s how it works: a diamond is composed of pressurized carbons. Conveniently enough, human bodies are about 18 percent carbon. Using about a pound of ashes, the company is able to distill out the carbon and use it to form a man-made diamond in a mold under high pressure in about a week. These synthetic diamonds created this way are often blue because of certain chemicals in the human body.
Algordanza, headquartered in Switzerland, offers a variety of diamond sizes and cuts that can be placed on a ring or other jewelry pieces. Prices run higher than conventional diamonds, starting from about $3,000 depending on the size and cut.
The resulting diamond will be “an everlasting keepsake, remembrance, or heirloom to pass to future generations,” Frank Ripka, CTO of Algordanza, told BusinessInsider.
LifeGem, based in Elk Grove Village, Ill., calls itself the original inventor and says it holds the U.S. patent for memorial diamonds. In a year, the company has “generally about a thousand customers worldwide,” a spokesperson from LifeGem told ABCNews.com.
LifeGem’s popular products, the company says, include the colorless LifeGem because it looks like the diamonds to which the public is accustomed. Blue diamonds are also in demand, the company says, because it is “difficult to get a blue diamond from nature.”
Diamond prices have fluctuated in recent years. From 2011 through 2012, overall prices for rough and polished diamonds declined by 14 percent and 13 percent, respectively, according to Bain & Company’s Global Diamond Report 2013.
Could synthetic Memorial diamonds be more worth than a natural diamond because of their sentimental value? Or is it a macabre product?
My answer, Not sure. What is yours?
Sample.
This is it folks, till next time.Bea :)
Sources:
www.geologynews.org
www.cbsnews.com
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