Cupriavidus metallidurans Bacterium used by Mitchigan State Professors to produce Gold Nuggets - BioChemistry Step Up Revolution for Cyanide Free Gold Mining

“Microbial alchemy is what we're doing, transforming gold from something that has no value into a solid, precious metal that's valuable”

Kazem Kashefi, Assistant Professor of Microbiology and Molecular Genetics at Michigan State University Thursday October 4^th 201

I will always be surprised by the ability of bacteria to do amazing things at the nanoscopic level. They can convert molecules from one form to the other, such as sugars into alcohol, organic material into Methane and even hydrogen as mentioned sparing in my blog article entitled  “UTECH partners with GOJ and UWI to develope Hydrogen Cooking Gas Cylinders - EU Funded 3 Year Project is Chasing Mavericks to push Jamaica into the Hydrogen-Electron Economy”.

But I’d never imagine a class of bacteria, Cupriavidus metallidurans existed that could convert toxic Gold (III) Chloride (Au₂Cl₆) into pure Gold (Au_(s)) nuggets after seven (7) days as stated in the article “Bling! Researchers create 24k gold in the lab”, published October 4, 2012 4:13 PM PDT by Christopher MacManus, CNET News. This is Biochemistry at its best folks, as I’m for the first time speechless and in awe of the potential of this discovery, despite its impracticality as a commercial process.

Professor Kazem Kashefi and Associate Professor Adam Brown are the evil geniuses behind this development. Their work was on display at the Prix Ars Electronica cyber Art competition in Austria between Thursday October 4th 2012AD to Sunday October 7^th 2012AD.

Aptly titled “The Great Work of the Metal Lover”, it consisted of 24-Karat Gold-themed equiptment that was being used in their research, a kind of Counter culture Art-Meets-Science exhibition consisting of a Glass bioreactor and the Cupriavidus metallidurans bacteria as shown below.

This is pure Biochemistry Art tinged with strong commercial possibility, to quote Associate Professor Adam Brown: “This is neo-alchemy. Every part, every detail of the project is a cross between modern microbiology and alchemy. Science tries to explain the phenomenological world. As an artist, I'm trying to create a phenomenon. Art has the ability to push scientific inquiry”.

This process may even go a long way to explain why panning for Gold (Au_(s)) was even possible, as presumably this bacterium was present in rivers and is responsible for Gold (Au_(s)) nuggets in river beds. Gold (Au_(s)), despite its relative unreactiveness as a Transition Metal, normally occurs in nature as a chemically combined Ore.

The regular process for extracting Gold (Au_(s)) involves dissolving it in Sodium Cyanide (HCN) that is used to produce an inorganic complex that precipitates out of solution and is easily separated by using Distilled Water:

4 Au_(s) + 8 NaCN_(aq) + O_2(g) + 2 H₂O_(l) → 4 Na[Au(CN)₂]_(s) + 4 NaOH_(aq)

According to the articles “Gold(III) chloride”, visited November 10, 2012, Wikipedia and “Aqua regia”, visited November 10, 2012, Wikipedia, Gold (III) Chloride (Au₂Cl₆) used as the food for the Cupriavidus metallidurans  is produced via one of two (2) methods in the Laboratory.

The first is via oxidation of Gold (Au_(s)) using Chlorine Gas (Cl₂) at 180 C at s.t.p (Standard Temperature and Pressure):

2 Au_(s) + 3 Cl_2(g) → 2 AuCl_3(s)

The second method involves several steps and is actually commercially viable with Ore with Gold (Au_(s)). Gold (Au_(s)) ore is reacted with Aqua Regia, a 1:3 ratio of concentrated Nitric Acid (HNO₃) and Hydrochloric Acid (HCl) to produce Gold (Au_(s)) with a valence of 3+ i.e. Au³⁺_(aq).

Aqua Regia is a mixture usually used to produce Gold (Au_(s)) of the highest quality:

Au_(s) + 3 NO⁻³_(aq) + 6 H⁺_(aq) →Au³⁺_(aq) + 3 NO_2(g) + 3 H₂O_(l)

Then the Au³⁺_{(aq) ­}is reacted with a Chloride Salt in the presence of Nitric Acid (HNO₃) to produce Gold Tetrachloride (AuCl_3(aq))  :

Au³⁺_(aq) + 3 NOCl_(g) + 3 NO⁻³_(aq) → AuCl_3(aq) + 6 NO_2(g)

AuCl_3(aq) + Cl^-_(aq) →AuCl⁻⁴_(aq)

Add a little heat, and Gold (III) Chloride (Au₂Cl₆) is the final product:

2 HAuCl_4(s) → Au₂Cl_6(s) + 2 HCl_(g)

The final stage involves using the above process instead involves no Hydrogen Cyanide (HCN)  and directly converts Gold (III) Chloride (Au₂Cl₆) directly into Gold (Au_(s)):

Au₂Cl_6(l) + Cupriavidus metallidurans = Au_(s)

By mere cursory glance, the practicality of making Gold (Au_(s)) via this method is revealed using Cupriavidus metallidurans bacteria! The reagents are a bit expensive, to be sure; protection from and recovery of Chlorine Gas (Cl_2(g)) will be very critical to the safety of staff at such a Plant and its overall success. But Economy-of-scale and the current prevailing high price of Gold (Au_(s)) on the Mercantile Exchange Markets should make it worth the while for an adventurous Investor to pursue the extraction of this noblest of Metals via this purely Organic, albeit corrosive method.

I’d love to see a scaled up version of this in Jamaica used to mine Gold, a venture in which the GOJ has shown interest in resuming back in July 2011AD in Pennants, Clarendon as noted in my blog article entitled “AUSJAM and the Pennants Gold Mine Rush - King Solomons Mines in Clarendon”. A revival of Gold Mining in Clarendon surely to bring out the prospectors in a Mining for Gold in Clarendon, Jamaica by a Bio-Chemistry Step Up Revolution (2012) for Cyanide-Free Gold Mining!