Sankt-Peterburgskie Vedomosti: St Petersburg scientists figure out how to increase an amount of mineral reserves
You may have been lucky to have found a gold nugget. Perhaps. Yet, it might turn out to be pyrite. It is called ‘fool’s gold’ as its colour is deceptively similar to that of a gold nugget, but it is not the precious metal. The nickname is nevertheless offensive, especially since pyrite is one of the most common hosts for gold in gold deposits. We discussed these issues with Olga Iakubovich, Associate Professor in the Department of Geochemistry at St Petersburg University, to shed some light on what the Russian subsoil is rich or poor in and on the prospects for mining in outer space.
Olga, the method that you and your colleagues have proposed enables us to ...
...determine the age of minerals. It indicates how promising a site may be for mineral exploration. Importantly, this method is quick and value for money.
Just over a hundred years ago, our ideas about the age of the Earth were quite vague. Today, there is an understanding of the Earth’s evolution and geological time scale: when and where certain mineral deposits appeared and how rich they are.
At the beginning of the 20th century, the British physicist Ernest Rutherford calculated the age of minerals from measurements of their helium contents. Helium is easy to isolate and to measure. Yet it turned out that on a scale of millions of years, minerals easily lost helium content. Due to volcanic activity and other geological processes, especially when the rocks are hot, helium quickly slips away into the atmosphere and escapes into the outer space. In the 1950s, this method was "buried". Yet in the 1980s, Americans used this method again, but for other tasks: to determine the age of mountains and other large geological structures.
At St Petersburg University, we have found out that there are minerals that retain helium. Among them are native metals, i.e. platinum, gold, and pyrite. Our method of isotope geochronology to measure the age of platinum nuggets is unique. Yet platinum is scarce, while pyrite is found in almost all types of deposits.
Imagine, a geologist analyses a rock. It contains inclusions of pyrite and other minerals, e.g. gold, silver, copper, or zinc to name just a few. Based on the age of the pyrite, we can determine the age of the ore deposits and assume how rich this exploration site can be in precious metals.
For example, we know that in a certain site, deposits that are 140 million years old are rich, and those that are 120 million years old are much poorer.
In this particular case, it makes sense to study in detail the site where the rocks are older. Small deposits, say a 1-ton gold deposit, are not economically viable. Investments in infrastructure, i.e. digging a quarry, attracting people, are irrational. What is economically viable is deposits that can be developed over decades. Is this simple method universal? Or do you have to develop other methods?
Determining the age of minerals with an accuracy of up to a million years requires other methods. Yet in most cases, much less accuracy is sufficient, and existing methods are very complex and expensive.
In one case, for example, you need to isolate minerals rich in potassium from a rock sample, irradiate it in a fast neutron reactor, wait six months for radioactivity decay, and only then measure it in the laboratory. Another method requires very complex chemical preparation and a large number of samples. Most often geologists only have a core in their hands. This is a small column of rock obtained by drilling. It is the size of a mug, but 400 milligrams of ore must be extracted from this rock sample. To this end, you must hit the vein.
Our method requires a substance with a volume of one cubic millimetre. Having analysed such a tiny sample, we need a day or two days to determine the age of the mineral. We are currently working to improve the accuracy of our method. In our methods, there can be an error of approximately 5%. Yet it can be decreased to 1.5%.
How did you come up with the idea to apply the method that everyone buried?
It all started with the Hermitage. As long ago as the 1990s. The museum experts were faced with the problem of counterfeiting ancient gold items. Geologically, we are operating by hundreds of millions of years. In this regard, archaeologists see no problems with the preservation of helium content as archeologically they are operating by shorter periods, i.e. some thousands of years. Loss of helium does not occur during such a short period of time.
Imagine, you have Scythian gold that could have been found in an ancient mound. No major geological processes occurred in the recent past: the rocks did not heat up, helium did not escape into the atmosphere, which means that the age of gold can be determined by helium content in minerals.
For some reasons, this approach has not been widely used by historians and archaeologists, but they have published several works. Years later, my supervisor, Iurii Shukoliukov, gained a deeper insight into this approach and told me to delve deeper into this topic as part of my master’s graduation project at St Petersburg University. A city design bureau developed a device according to our technical specifications. We tried to study natural objects, and it became clear: helium also does not escape from other minerals.
If the method is simple, it is going to gain popularity. Especially, if an accuracy of tens of millions of years is sufficient. Or is there some kind of a "secret" in your method?
Anyone can use our method. Our project is a fundamental research project. It is supported by the Russian Science Foundation. Yet there is a know-how: it is a Russian device adapted to solve this problem. Even Germans and Swiss ordered a similar device in Russia. It is quite unusual as we purchase equipment from Europe.
How quickly did subsoil users adopt the method?
Very quickly. We received our first scientific and commercial orders about 12 years ago, mostly from international subsoil users. Russians are much more conservative and our scientists and subsoil users were quite happy with the Western methods, although they were still far from being accurate. Then, Russian companies got involved surprisingly quickly. Today, we cooperate only with Russian private and public organisations, in particular with the Central Research Institute of Geological Prospecting for Base and Precious Metals (TsNIGRI). They are very interested in applying the results of our fundamental research in practice. It saves resources and time. In general, our research results are a huge step forward.
Is it value for money?
The question is not easy to answer. By following the scientific approach, it is estimated that 2 to 3% of geological exploration can be saved. Our method can save half a percent. It may seem extremely small. Yet geological exploration is an incredibly expensive business, billions of roubles. Even this half a percent turns into millions.
In terms of platinum reserves, Russia is among countries that take the lead...
We are the first in the world in reserves of palladium, a precious platinum group metal. It is needed in the automotive industry, i.e. palladium-based catalysts for exhaust aftertreatment.
We are second in platinum, second only to South Africa. There is also a large deposit in Canada. It is quite unusual, i.e. in the crater that was formed from a meteorite that fell about 2 billion years ago. However, South Africa and Russia probably hold 90% of the world market for platinum metals. Platinum is an extremely rare metal. Do you know what is generally referred to as a largest deposit? It is at least half a ring of platinum that can be extracted from a rock with a volume of, say, a classroom.
In Africa, platinum is concentrated in a small horizon layer, i.e. 15 cm thick, which stretches for tens of kilometres. In Russia, the situation is different. There were the famous Ural placers. Nothing could be cheaper to mine, take a shovel and rake up the nuggets. Platinum began to be mined in the Urals in the 19th century. Until the 1920s, before the discovery of South African deposits, we were the world’s leading supplier of platinum to the world market.
Today, the placers are almost all worked out. We have to extract platinum from primary deposits. It is much more expensive. If nature has crushed everything in alluvial deposits, you have to blast the rock, crush it, differentiate it and extract what you need. This is the case, for example, in Norilsk, where platinum is contained in sulphides, i.e. large shiny bodies from which copper and nickel are mainly mined, along with platinum and palladium. Norilsk platinum will last for a long time. Yet the industry is developing, which means that the demand for platinum group metals will only grow. Platinum is used for catalysts for many chemical reactions. We will have to find new exploration sites.
Are natural reserves considered to be what we can find in the subsoil? Or are natural reserves only what can be quickly extracted if necessary?
A reserve is something that we can reach. Importantly, it is not always profitable to mine these minerals.
Currently, there is a lithium boom in the world. We have very large lithium deposits in the Kola Peninsula. Yet all countries, including Russia, buy lithium from Chile. Chile has lithium reserves in brine. Lithium is mined through extraction from bine, which is easier and more cost-effective. You scoop up some water, evaporate it, and you get pure lithium. What is hard rock lithium extraction in the Kola Peninsula? You need to take a rock, crush it, spending energy on it, separate it, and dissolve it. Or take, say, uranium. Russia has many uranium reserves. Yet uranium is mostly found in solid rock, i.e. the crystalline foundation.
In general, it is cheaper to buy. Yet if we have to extract uranium "at any cost", we can do it.
By the way, I do not exclude that in the near future countries that were previously "uninteresting" from the point of view of mineral resources may become serious players in the global market. The status of resources is changing. For example, gallium and indium are now needed in microelectronics and semiconductor manufacturing. They have become strategic. Yet previously they were so unnecessary that gallium was not always indicated in geological reports. They drilled the deposit, wrote down how much aluminium, copper, zinc it contained, but indium or gallium were "not taken into account".
The situation is also changing when it comes to more familiar minerals. For example, wind industry is the most copper-intensive renewable power technology sector. Copper is used in cables. In wind industry, there is a rising demand for copper. Yet most reachable deposits have already been found. Other deposits are in remote, forested, swampy regions. If we are lucky to find a promising rock there, we need to get as much information from it as we can. To this end, we need methods that are cheap, simple and fast. Our method provides just such an emphasis.
The situation is the same with rare-earth elements. There was no demand for the rare-earth elements. Yet today they are critical for high technology and the military industry. The main global supplier of rare earths is China. Figuratively, if China says tomorrow: "We stop selling rare-earth elements", the whole world will sit still and think: what to do?
And what shall we do?
Even international experts say that Russia has a clear and coherent policy in this regard. We are compiling a list of strategic minerals. Since the Soviet Union, we have our own reserves for everything we need. These reserves are explored and calculated. Among them are even those that are still unprofitable to extract.
Roughly speaking, if Chile suddenly stops selling us lithium or China stops selling rare-earth elements, we will not be negatively affected. We have our own raw materials, yet they are more expensive to extract.
Is Russia rich in mineral resources just because its territory is huge, or are we lucky in some other way? Say, like Canada with its meteorite.
The first reason is the large territory. This territory is incredibly diverse: mountains, and ancient foundations. The second reason is that the Soviet Union did a lot to ensure that these riches were found. Geologists were given a document: "to provide all possible assistance", and during their expeditions they could ask "on the spot" for transport, petrol, and workers. The whole country was ploughed up. The current balance rests on the shoulders of those people who have trampled thousands of kilometres with a hammer.
Nowadays, of course, there are no such favourable conditions. No one will mine an element if there is no one to sell. If we do not currently have our own consumer, then before extraction we need to ask who intends to buy it from us. It is a complex geological economy. Still, the task of geologists is to provide the very opportunity to increase the amount of reserves with the minimum investments. Not to rely only on what has been done by previous generations.
The topic about mining beyond the Earth is gaining a popularity. How realistic is it?
The most famous are three global projects.
The first is the search for minerals on Mars. We will need minerals to build a station on Mars in case of Mars colonisation to avoid a situation when we have to bring everything from Earth. Yet the question is: are the current remote sensing methods reliable in identifying the place, say, in the Eagle Crater where to build a station as there is a lot of iron there? Perhaps, by the time of Mars colonisation we will need something else, not iron. Completely different technologies may as well appear.
The second project is a little curious. It is mining platinum group metals from asteroids. Most meteorites orbit between Mars and Jupiter, some of them do not fall anywhere. On the one hand, they therefore pose a threat to the Earth, but, on the other hand, they seem to be a promising source of minerals. For example, an iron meteorite consists of iron, nickel and a lot of platinum group metals. Of course, it is tempting to take a piece and deliver it to the Earth. Yet the risks are big. If something goes wrong, a large fragment could hit the Earth.
The third project is Helium-3 mining on the lunar surface. This rare chemical element is needed for industry, and in future, it will be needed for thermonuclear processes. There is a lot of Helium-3 on the Moon. Yet is it feasible to deliver? We need technology. No technologies, no deposits.
Do you, as a geologist, have your favourite stone?
Labradorite. It is stunning. It is glowing from the inside.