Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


No gold without microbes


Many people love jewelry and other items made of gold. They have inconspicuous microbes to thank for this: Three billion years ago they held the noble metal in the Earth’s crust. This is the opinion at least of an expert from the University of Würzburg.

All the Earth’s gold deposits should actually be in the Earth’s core – buried deep out of mankind’s reach. After all, this metal has such a high density that in the course of the creation of the Earth it ought to have been moved to there. But in actual fact it also accumulated in the Earth’s crust.

Carbonaceous layer of sediment rocks, essentially consisting of kerogen, Witwatersrand basin, South Africa: an extremely rarely well preserved remnant of mats of microbes performing photosynthesis.

(Photo: Hartwig Frimmel)

Why did the gold stay there? “To this day this remains one of the most hotly debated issues in geology and geochemistry,” says Professor Hartwig Frimmel, chairman of the Department of Geodynamics and Geomaterials Research at the University of Würzburg. He is now adding a new theory to the debate, which suggests that prehistoric microbes are responsible for binding gold to the Earth’s crust.

Frimmel presents his idea in detail in the journal “Mineralium Deposita”. The Würzburg scientist is regarded as the world’s leading expert in gold deposits. He spent a long time as a professor at the University of Cape Town conducting research in South Africa’s Witwatersrand region, among others. This is where the world’s largest concentration of gold in the Earth’s crust can be found.

Where there is a lot of gold, there are also the remains of bacteria

What do microbes have to do with gold? “Wherever there are large quantities of gold, there are also layers of stratified carbonaceous substances that are of biological origin,” says Frimmel. “We have found evidence to suggest that these are the remains of cyanobacteria.” These original microbes inhabited the coastal regions of the Earth three billion years ago.

The cyanobacteria were the first living organisms that performed photosynthesis and first created “whiffs of oxygen”, as Frimmel says. The Earth at that time was still largely hostile to life: Rain had roughly the acidity of vinegar, and the surface water was rich in hydrogen sulfide.

Where there was oxygen, gold was bound

“But under precisely these conditions gold becomes extremely soluble in water,” explains the professor. The rivers and other bodies of water must have been very rich in gold back then. Where this water came upon colonies of cyanobacteria arranged into mats, the gold was chemically adhered to the surface of the microbes immediately by the oxygen.

So, three billion years ago a kind of “Gold Mega Event” occurred: “The chemical conditions at that time were perfect for binding gold and enabling the formation of deposits,” believes Frimmel. Over time and in this manner, for example, the huge gold deposits were created that can be found in such places as the Witwatersrand region of South Africa. At one time 100,000 tons of the treasured metal were stored there. More than half of it has already been mined.

“First whiffs of atmospheric oxygen triggered onset of crustal gold cycle”, Hartwig E. Frimmel, Quinton Hennigh, Mineralium Deposita (2015), DOI: 10.1007/s00126-014-0574-8


Prof. Dr. Hartwig Frimmel, Department of Geodynamics and Geomaterials Research, T +49 (0)931 31-85420,

Weitere Informationen: Prof. Frimmel's research

Robert Emmerich | idw - Informationsdienst Wissenschaft

More articles from Earth Sciences:

nachricht UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine

nachricht Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>