Pyrite is infamous in the world for its resemblance to gold. As a result, it is often called as ‘Fool’s Gold’. Though it has the same color as gold it holds no significant preciousness as the original metal. The term gained popularity in the 1840s when California gold rush occurred and inexperienced people would claim that they had landed on huge piles of gold that was actually pyrite. However, a group of scientists recently discovered that Fool’s Gold isn’t completely valueless.
Fool’s Gold or Pyrite actually contains tiny amount of gold that cannot be easily extracted. This gold is also called as ‘Invisible Gold’ as observing it within pyrite requires complex scientific devices. The researchers believe that the finding may help gold miners in extracting the gold from Pyrite in highly efficient and sustainable ways like bio-leaching. The gold in pyrite is difficult to extract owing to the fact that it is located in the crystal imperfections which are very very small in size. To locate these imperfections the scientific team made use of a special device called Atom Probe. The Atom Probe can perform analysis of materials at very high resolutions and thus can locate the crystal imperfections precisely. This is possible as it has the ability to develop a 3-dimensional map indicating the precise areas where impurities are located in the crystal structure. These impurities is where the invisible gold is present.
Denis Fougerouse, the lead author of the study, in an article on the Conversation stated, “This is particularly common where the crystals have been twisted during their history; here, gold can be present at concentrations several times higher than in the rest of the crystal”. The scientists are of the opinion that the ‘decoration’ of the pyrite crystal with gold atoms is highly usual where twisting has occurred during the history. In such cases, pyrite contains high concentrations of the precious metal in a bonded form. The scientists also disclosed that due to the presence of gold at imperfections within the pyrite crystal, enhanced partial leaching may pave way for bacteria to destroy the crystal and release gold. Thus, bioleaching may provide a new method to save energy while extracting gold at large levels. However, this idea is yet to be tested but can have significant energy savings.