New type of gold can now be extracted from fool’s gold
Fool’s gold is a type of mineral pyrite that got its nickname because of its deceptive looks. It looks very much like actual gold but it isn’t. This term first emerged in the California gold rush in 1840 because a lot of inexperienced prospectors claimed discoveries when the reality was all that they had was pyrite composed of iron disulfide that looked like gold at first glance, but actually wasn’t. Pyrite crystals can contain a bit of gold but gold within pyrite is hard to extract, or to see which is why it is referred to as “invisible gold”, as it cannot be seen with a microscope.
Some research has shown that when pyrite crystals are formed under extreme temperature and pressure the develop small imperfections “decorated” with gold.
Previously, it was thought that gold in rich pyrite was in fact formed in a multi-step process, which would suggest that pyrite and gold within the pyrite each crystallised at different times and later clumped together. However, scientists have found gold can “decorate” imperfect pyrite crystals In a single process. Why does this matter?
Scientists have long wondered about how gold can be extracted from pyrite in a cost effective way given how miniscule it is. As we inch closer to peak gold, there will come a time that conventional gold mining will have to give way to other types of mining. Scientists are revisiting their theories about gold mining in general. Currently, the amount of old that is still yet to be mined is estimated to be approximately 50,000 tonnes. To date, the amount of gold that has already been mined is about 190,000 tonnes. Gold is not abundant, nor can it be created which means it will always be valuable.
Since the appetite for gold shows no signs of waning, geologists have had to investigate other ways to meet the demand for gold and fool’s gold has come under the microscope. So far, it looks like we will have to stop seeing gold in pyrite as being merely “decorative” but useful. The problem with gold inclusions in pyrite crystals its extraction requires a lot of energy. However, scientists and metallurgists have been looking at efficient ways of extracting gold from pyrite in a way that reduces greenhouse emissions.
Dislocations within pyrite crystals could make partial leaching of gold possible. Also, they can offer targets for bacteria to breakdown the structure of the crystal thereby releasing the gold. This process is known as bioleaching. This could potentially reduce the energy consumption for extraction off gold from pyrite crystals. This idea isn’t being used currently but it is definitely being investigated. These theories and scientific explorations can help pave the way for sustainable gold mining. It might turn out that fool’s gold isn’t as foolish as it has been regarded. In fact scientists have discovered that pyrite can be a significant indicator that there is gold nearby. This is how some prospectors were able to find large deposits in certain areas. However, for now pyrite will remain fool’s gold until better, effective and environmentally sustainable processing techniques are found.
This article was brought to you by
Shop 3a, Level 3 /
144 Adelaide St, Brisbane
QLD 4000
(07) 3123 6677