The diamonds were located inside of zircon, a mineral whose chemical name is zirconium silicate (ZrSiO4). They were probably created by the pressures exerted from about 100 to 150 kilometers of crustal rock above.

The research study, led by geologist Martina Menneken, of the Institute of Mineralogy, University of Munster, Germany, appears in the August 23, 2007 issue of the journal Nature (448, 917-920). The other collaborators in the discovery include Alexander A. Nemchin, Robert T. Pidgeion, and Simon A. Wilde, all of the Curtin University of Technology, Bentley, Western Australia, Australia; and Thorsten Geisler, also of the University of Munster.

The article’s title in Nature is called “Hadean diamonds in zircon from Jack Hills, Western Australia”.

Their abstract states: Detrital zircons more than 4 billion years old from the Jack Hills metasedimentary belt, Yilgarn craton, Western Australia, are the oldest identified fragments of the Earth's crust and are unique in preserving information on the earliest evolution of the Earth. Inclusions of quartz, K-feldspar and monazite in the zircons, in combination with an enrichment of light rare-earth elements and an estimated low zircon crystallization temperature, have previously been used as evidence for early recycling of continental crust, leading to the production of granitic melts in the Hadean era. Here we present the discovery of microdiamond inclusions in Jack Hills zircons with an age range from 3,058 (plus/minus 7) to 4,252 (plus/minus 7) million years. These include the oldest known diamonds found in terrestrial rocks, and introduce a new dimension to the debate on the origin of these zircons and the evolution of the early Earth. The spread of ages indicates that either conditions required for diamond formation were repeated several times during early Earth history or that there was significant recycling of ancient diamond. Mineralogical features of the Jack Hills diamonds—such as their occurrence in zircon, their association with graphite and their Raman spectroscopic characteristics—resemble those of diamonds formed during ultrahigh-pressure metamorphism and, unless conditions on the early Earth were unique, imply a relatively thick continental lithosphere and crust–mantle interaction at least 4,250 million years ago.

The discovery amazed and perplexed the scientific community and even their discoverers. Simon Wilde declared, "It came out of left field and we weren't expecting it.”

The discovery already has provided scientists with interesting findings. For one, the discovery suggests that the rocky crust of the Earth was thicker early in its history then was currently thought.

It also has shown that plate tectonics, the movement of Earth’s crustal plates, were already underway at the time these diamonds were created.

The diamonds also contradicts the currently accepted speed by which early Earth cooled down. The diamonds indicate the Earth cooled down faster than what is today thought.

Although this discovery has very interesting implications to the creation and early evolution of the Earth, scientists still need to verify and confirm this new information.


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