The world's leading mineralogist Jakub Plášil has been unravelling complex crystal structures and discovering new minerals for years. At first glance, it might seem that this is a marginal area of science that is not "in vogue" today. Yet Plášil and his colleagues are making discoveries that have broader implications – for example, in understanding how uranium and other metallic elements are distributed in nature. His research has won him an award by the European Mineralogical Union.
When you say mineralogy, people often think of the showcases at the National Museum. Is it a pleasure for you to walk among them?
I've loved it since I was a child. I used to go there with my parents and always only to the mineralogical collections (laughs). At that time, the others were beyond my interest. I had the opportunity to see the collections during the reconstruction of the building. They were moved to the depositories of the museum in Horní Počernice, and my colleagues spent an impressive amount of time cleaning them, preserving them and then re-arranging and selecting minerals for the newly arranged permanent exhibition. But I must admit that after the reconstruction I have only been there once, although I have been cooperating with the National Museum in research for a long time. When I have a spare moment, I prefer to go for a walk in the forest and take pictures to get a completely different impetus, otherwise I would be surrounded by "rocks" all the time.
In July, you will receive the European Mineralogical Union's major award – the EMU Research Excellence Medal 2024. Were you surprised to hear that you will get the award?
Honestly, I didn't expect it, because I'm involved in things that are not exactly mainstream. Surely, I do transdisciplinary and multidisciplinary research in classical crystallography, but many people consider it as obsolete. And we don't advertise too much that we perform top-quality research, so I didn't expect anyone in the world to notice.
Sometimes a little more conservative approach and defiance is necessary, if only because the field of mineralogy is gradually disappearing from university study programs. And that is a great pity. We are losing part of our know-how, part of our common knowledge.
I consider the award to be mainly a recognition of Czech crystallography and mineralogy because this field has a very long tradition here, since the second half of the 19th century. I am very proud to be able to continue this, to develop the discipline and to do what I believe is important. Sometimes a little more conservative approach and defiance is necessary, if only because the field of mineralogy is gradually disappearing from university study programs. And that is a great pity. We are losing part of our know-how, part of our common knowledge.
You are mainly concerned with mineral structures and structures of inorganic substances. You study why, where and under what conditions minerals are formed. What is classical crystallography in your understanding?
Recently, I have been studying minerals that have been known for fifty or a hundred years and yet no one has described their complex structure. And even modern methods, which have undergone tremendous development in the last 20 years, have not helped. By leaving the structure unknown, we are missing quite important information that is crucial for understanding and determining some other physical and chemical properties, such as solubility.
A neglected but important intuition
Is it worth spending years studying the structure of a mineral that only a few people on the globe are interested in?
When we manage to decipher the structure, we also advance the computational methods used for deciphering. By discovering a new "computational trick" and optimizing the computational method, we have simplified the solution of hundreds of other structures in our Jana program, which has been being developed by Václav Petříček for more than 30 years. For years you have been trying to discover where the shoe pinches. Such as in the case of complex twinned structures. Or figuring out why a complex modulated structure defies solution, which provides a very complex diffraction picture that we are able to use to solve the structure. Then you get an idea, or come up with a little thing that helps you uncover the whole thing, and you're done in a flash. Not in a flash, I'm exaggerating.
How many people in the world are dedicated to solving the complicated structure of minerals?
There's, like, ten crystallographers in the world studying them. They often work on a specific group of substances, like the complex structure of sulfosalt minerals. A long time ago, I did ore mineralogy, and I was interested in sulfosalt minerals. Then, while I was in college, I got into hexavalent uranium minerals and structures, which are fascinating and important for many reasons After 15 years of studying these substances, a colleague and friend approached me to see if I could help him with a complex structure of a lead sulfoarsenite/sulfoantimonide that no one was able to help him with at the time, and I agreed. So I went back and got into a little bit of the crystallography of these compounds and now I do both. Both sulfosalts and oxysalts. Few people in the world do that, and I'm not exaggerating.
Do you have a favourite structure you've solved recently?
I've managed to solve a number of interesting structures in the last two years. We're finishing about six publications now. As an example, a mineral that was first described in Africa in the 1980s. It didn't have a known structure, but even from the initial description it looked like it was going to be quite a challenge because it has a very 'wild' chemical composition – it is a hydrated uranyl carbonate silicate that contains rare earth elements, especially gadolinium, and calcium.
This mineral forms extremely long needles, actually very thin and elongated tabular crystals. To give you a better idea, such a crystal is a millimetre long, but its thickness is a thousandth of a millimetre. It's a very fine fibre, and it's terribly easy to bend, to distort. However, this makes it impossible to determine the structure, because when you bend the crystal, you simply literally break the structure locally.
How did you go about it?
Using diffraction on a very strong X-ray source, I was able to determine that although the filament looks and behaves uniformly like a single crystal, it is actually made up of thousands of other individuals. Thanks to afomer colleague from our department, Gwladys Steciuk, I was able to determine the structure using electron diffraction. We have a structural model that is not perfect, but it is not and will not be any different. To some extent, it's still a significant approximation. But while studying it, we've run into some limits that are dictated by the variability of every single nanocrystal studied. That variability is primarily dependent on the slightly different molecular water content of the crystal. And that's enough to make each crystal behave a little differently. Measurements of more than two dozen crystals and thousands of experimental images were processed. This processing took two years of computational operations.
Do you feel that artificial intelligence will facilitate research in your field?
Artificial intelligence is of course a big topic today and that I don't quite understand it deeply. That's why I'd rather try to shift my focus back to us humans, not machines. My experience tells me that in science the role of intuition is terribly important, but also overlooked and underestimated. It helps to direct us where to go with our research. I can't say how much such a skill is replaceable by artificial intelligence. On the other hand, it also seems to me that the human factor is important precisely because of the inherent presence of errors. These seemingly nonsensical errors will often show you alternative paths or something you missed during calculation or research, etc.
Diffraction is a physical phenomenon in which radiation is scattered at periodically arranged points, such as atoms in a crystal, to determine its structure. There is electron, neutron or X-ray diffraction. In 1914, German physicist Max Theodor Felix von Laue was awarded the Nobel Prize in Physics for his discovery of X-ray diffraction on a crystal. One of the world's most famous diffraction images is that of DNA, taken by British scientist Rosalind Franklin, from which Francis Crick and James Watson then determined the structure of the DNA double helix, for which they won the 1962 Nobel Prize in Medicine (Rosalind Franklin died in 1958, she did not win the Nobel Prize). In Czechoslovakia, the pioneers of X-ray structural analysis were Bohuslav Ježek, Adéla Kochanovská and František Ulrich.
Systematic work contributes to knowledge
Are you a renaissance man?
(Laughs) Yeah, I've heard that before, but I think it's a bit of an exaggeration.
Where does the desire to deal with the unresolved come from in you?
I could use pathetic wording and say that I am trying to contribute my actions to the advancement of humanity and knowledge, but I often ask the question myself, especially when I am frustrated. It helps me to realize that what I am doing is good and important. Of course, I will not hide the fact that it is exciting to discover hidden patterns and unknown substances. To some extent it pleases the ego, and when something goes well, it is of course pleasurable and needs to be admitted. It's like discovering a new star and it gives you a special feeling. Exciting, but uplifting at the same time. You realise that you are discovering and seeing things that no one has ever seen before.
Making a discovery that could be called "big" without kidding is becoming terribly difficult. The unexplored space is rapidly diminishing and we are focusing on smaller and finer details. That is why it is necessary to learn enjoying the little things.
On the other hand, making a discovery that could be called "big" without kidding is becoming terribly difficult. The unexplored space is rapidly diminishing and we are focusing on smaller and finer details. That is why it is necessary to learn enjoying the little things. The big, ground-breaking discoveries, such as radioactivity or the wave function, have already been made. Now we're piecing together the same mosaic in a subtler way, doing work on finer details. Even if it seems like bizarre little things that seem insignificant, it's good to realise that it's moving science forward again. But even here, every once in a while, an amazing discovery unexpectedly appears I am referring, for example, to the discovery and description of altermagnetism by the team of Tomáš Jungwirth, which came from a base of extremely tedious, systematic and long-term work in the field of antiferromagnetism. Systematicity and continuity are two things that I would like to mention and emphasise as extremely important elements inherent to high-quality research. And they make botheffective and it often leads to success.
Is discovering new minerals more satisfying than deciphering their structures?
There is an unofficial race in the world of science to see who can describe the highest number of new minerals. I gave in to it for a while, but I think I sobered up quickly. I've been involved in the description of more than 120 new minerals, and it should be emphasized that 99 percent of the time it's a team effort.
One of the first mineralogists to study mineral structures by modern X-ray diffraction was Anthony Kampf of the Natural Museum of Los Angeles County. He has discovered about 500 minerals. He works extensively with local collectors in the States who give him specimens to research. I've been working with him for a long time on measuring the optical properties of minerals, which very few people can do these days. Nobody really wants to do it because it's a laborious business with an optical microscope. You have to have a trained eye for it and sit with it. Tony, on the other hand, is using my experience as a uranium crystallographer.
We call something crystal clear something that is obvious and undeniable. In our minds, a crystal is transparent, brilliant and beautiful. ...
What do you consider your most important discovery?
Over the last 12 years we have managed to expand the group of known hexavalent uranium sulfate minerals. They are small, yellow or orange crystals, all looking the same and difficult to work with at first sight. No wonder they were thought to be the same, given the difficulties in characterisation. Originally, eight known minerals found in nature have turned out, thanks to our research, to be forty-five incredibly chemically and structurally different substances. And that is certainly not the final number! We now have an idea why they're found at certain places. We know that some arise from extremely acidic solutions, while others are almost "drinking water". This achievement was possible only by twelve years of systematic research, during which colleagues in Northern America collected and identified samples, sorting out those with known structures from those with unknown ones, while we have solved their structures and measured vibrational spectra. This research has shown how important that systematic work is.
You take photographs in your spare time, but you use a less common technique of photographing forests, reverting to analogue and black and white photography. What inspired you to do that?
I actually use both. Both digital and analogue. Each format requires something different and allows something different at the same time. Because of the high resolution, I use digital photography as a basis for making matrices for photogravure, which is an "analogue" printing technique that, while it wipes out a little, preserves the resolution of the original photograph in some ways.
I returned to analogue or film photography after years of completely digital work. As a young man I used to shoot on film, and in recent years I have been shooting on roll film and a panoramic format called noodle. The latter in a way both reduces and expands the view of the world. Especially when you are shooting portrait orientation. The tonality of black-and-white large-format photography is unmatched – soft, unrefined, and very artistic.
In the woods you wait for the best light. What time do you have to set out?
Most of the time I shoot in the Boubín National Nature Reserve, and if I can, I go before dawn or stay in the forest until dark. The trees get a completely different volume and the forest space. You perceive it in a completely different way. A lot of things are only hinted at, not finished.
Jakub Kopecký Plášil was awarded the prestigious EMU Medal for Research Excellence in 2024 by the European Mineralogical Union. His research focuses on the structural analysis of complex crystalline materials using diffraction methods His work has contributed significantly to the understanding of uranium minerals and nanocrystalline phases in nature, leading to the discovery of previously unknown minerals. He has thus fundamentally expanded knowledge of the oxidation and weathering processes of uranium deposits and their influence on the mobility of uranium in the geo- and biosphere. His book Jáchymov– Mineralogická perla Krušnohoří (Jáchymov – the Mineralogical Pearl of the Erzgebirge) earned him a nomination for the Magnesia Literature Prize for Science Literature in 2020. In addition to science, he is also a photographer, especially capturing the beauty of trees and old-growth forests (In 2022, he published a book of photographs entitled Prales pod Falkenštejnem (The primeval forest below Falkenstein).