Coring is celebrating its 10ᵗʰ anniversary in 2026. So, the editorial team decided to interview our founder, Grigor Topev, for the first issue of the year.
Grigor Topev is the founder of Coring Magazine, a globally recognized publication in the mineral exploration drilling industry.
He has a Master’s degree in drilling engineering, combined with over 20 years of field experience across multiple continents. Across his career, Grigor has participated in numerous complex drilling projects and has worked extensively on R&D initiatives in directional drilling, deviation control, and drilling technologies in general.
He is also the Co-Founder and Managing Director of BG Drilling Solutions.
First, tell us about your education and life before drilling. How did you choose that as your career path?
Grigor Topev: Back in the late 1990s, young people in Bulgaria could still attend university for free, and a large percentage of them took advantage. After graduating from the math high school in my hometown, I too followed this path; it was natural back then. I had set my sights on a major related to firefighting because I really liked that kind of profession. Life, however, had other plans for me… So, I ended up, quite by chance, at the University of Mining and Geology in Sofia, which I hadn’t even heard of at the time. There, I enrolled in the ‘Oil and Gas Drilling’ program—something completely unfamiliar to me, but which sounded quite interesting. I quickly realized that this was exactly the right thing for me.
Could you share some insights into the beginning of your career and your professional journey?
Grigor Topev: After completing the final semester of my Master’s degree, I started looking for a job in my field. The problem was that I didn’t know anyone in the industry, nor did I have any university references. At the time, I was working night shifts at a small kiosk in front of the Sofia Printing Works (most newspapers were printed there). People from the facility were constantly offering me newspapers, and I always refused because I didn’t like reading them.
One evening, when I’d decided to look for a job, I asked an acquaintance from the plant to bring me a newspaper so I could look at the classifieds. And as soon as I opened the paper, I came across an ad seeking someone from the University of Mining and Geology. There were no details about the type of work; only a phone number was listed. There are many majors at the university, and the chances were slim, but the next day, I called anyway. As fate would have it, they were looking for two guys who had graduated in drilling and spoke English for a cementing job in Libya.
So, at the age of 23, another friend and fellow student (Petyo Toshev—Baroid) and I found ourselves deep in the Sahara Desert, where we spent four months. It was an unforgettable experience, not only because of the desert’s incredible nature and the breathtaking views of sunrise and sunset, but also because of the challenges I faced as a young man away from the comfort of home for the first time.
When we returned, my university professor, Assoc. Prof. Shteryo Lyomov (now my long-time business partner) had heard that I had returned from Libya and invited me to join Devico’s then-emerging field team. There, I spent several formative years building hands-on experience in directional drilling, first as a field operator and later as a global operations manager. I learned a great deal during that time and remain grateful to Devico and its founder Viktor Tokle for the opportunity.
Following those years, Shteryo Lyomov and I founded BG Drilling Solutions with the idea of developing directional tools based on different principles, and we have been on that adventure ever since.
Tell us what inspired you to launch Coring Magazine.
Grigor Topev: As a young guy, I was very enthusiastic and a big fan of drilling and what I was doing; maybe I still am, but today with more realism than pure enthusiasm. It pushed me to connect with more people in the industry and to look for a space where ideas and experience could be shared. That’s when I created the LinkedIn group Diamond Drilling for Mining & Mineral exploration. At first, the group was very popular and highly active. It was the only place to share such information. I carefully screened the people who joined, and its purpose was entirely non-commercial—to provide a space for purely technical drilling discussions.
Over time, however, activity began to decline, which is completely normal. That’s when I told myself that if I wanted this effort to continue, it would have to take on a different form, one that depended more on my own actions than on the activity of others.
So, in late 2015, already committed to various work responsibilities, with young children and limited time, I founded Coring Magazine.
What were the first years of Coring like?
Grigor Topev: I knew this initiative could easily turn into a failure—an international magazine published by an enthusiastic young Eastern European would naturally face a lot of skepticism, and even prejudice. So I had a strategy. As I am not a native speaker and, at that time, had zero editorial experience, I knew I had to bring someone on board to be the face of the magazine and help resolve the language issues I might have. So, I went out and found a freelance native English editor.
The second part of the plan was to create a really good-looking product. I started looking for a graphic designer, because the visual identity was extremely important. I went through many—and here I truly hit the jackpot. Ivan Ginev from Cog Graphics did a fantastic job, and that visual identity became a major strength of the magazine. It seems the strategy worked, as this edition marks a decade of Coring Magazine.
I remember that the magazine preparation was an incredibly varied process, and I had to handle many different tasks. For example, I would go to the print shop and load my old Peugeot 306 with about 2000 copies of the magazine. Then, with the help of my wife and children, we would put each magazine in an envelope, print the labels, and prepare all the copies for shipping. Every single magazine passed through our hands.
What really helped me in the beginning were a few people from the industry. I didn’t even know them personally, and I suppose they didn’t see much potential in my venture, but they chose to help and didn’t want to dampen the enthusiasm of a young person—something good people do. These people supported the magazine with advertising and content, and thanks to them, it weathered the most critical moments.
It wasn’t until three years later that the magazine managed to break even for the first time, and only after a few more years did it start generating a modest profit.
How do you see the magazine today?
Grigor Topev: I am proud to say that today Coring Magazine is an established and well-recognized media outlet in the industry. I believe it is the only one that reaches a wide range of drilling professionals, nearly all decision-makers in the industry, and many exploration geologists.
Here I’d like to highlight the efforts of the current Coring team—Martina Samarova, Maksim Mayer, Adelina Fendrina, Elena Dorfman. They are truly amazing and the real reason behind its success. These days, I’m just the guy who slows them down with my late responses, in the rare cases when they actually need to hear from me.
And we’re also truly fortunate to have Brett Davis on board as a consulting geology specialist and Section Editor. Brett is such a great name in structural geology, and his contribution has been invaluable in maintaining the high quality of our geology section and keeping it technically strong and relevant.
What challenges does the magazine face?
Grigor Topev: The biggest challenge has always been the same: sourcing enough material, advertising, and keeping the financial side sustainable. It’s generally very difficult to get people in the industry to share, write, and speak up. The industry is quite closed in the sense that everyone tends to operate on their own. Everything has become too cautious, too guarded, and too business-oriented.
Take, for example, our most-read piece, the Annual drilled meters statistics. Readers have no idea how difficult it is to collect that data. Many companies still choose not to participate, which makes the statistics incomplete. With real support and participation from the industry, we could go much further, tracking active exploration projects, monitoring the number of operating rigs by country, following trends over time, even building reliable benchmarks such as price-per-meter across regions. This kind of transparency would be extremely valuable, but at the moment it remains out of reach.
If this industry wants to have a voice, it has to support the platform that carries it. Advertising is what keeps the magazine alive. If Coring is to deliver more diverse, broader, and more useful information, it will require more advertising, more shared knowledge, more real data, and more real experience.
So this is a direct ask in two directions. To the companies, if you have the capacity to support, support the magazine. And to the professionals, if you have something worth saying, say it. You don’t need to be a writer, that’s our job. What we need from you is the substance, the experience, and the willingness to contribute.
Do you have a favorite issue?
Grigor Topev: I don’t have a favorite issue, but I have many favorite interviews. One of them is with Harvey Tremblay (Issue 22) and his story of how he was fixing up a drill head on their kitchen table. Things like that impress me. Another favorite is the interview with Craig Scott from one of the very first issues of the magazine (Issue 2).
Let’s talk about your area of expertise, directional drilling. What can you tell us about it?
Grigor Topev: Directional drilling has been on a steady rise over the years. It is no longer some exotic technology or a necessary evil reserved for special projects. It is becoming increasingly accessible, increasingly popular, and an integral part of the drilling process—and this trend will continue. The reason is simple: targets are getting deeper, programs more complex, and geologists are increasingly aware of what this service can deliver.
The problem is that there is also a lot of hype and speculation around directional drilling. Companies often focus on a single tool and present it as a universal solution. In my view, this is a mistake. The focus should not be on ‘our tool is the best’ but on ‘which tool is the most suitable for this project’. One project may require a simple steel wedge, another a downhole motor, and a third—something more advanced. There is no universal tool that performs equally well in all conditions.
Another issue is that directional drilling is often offered regardless of whether it truly makes sense for the program. When the client is not fully aware, and the provider is simply looking to secure another job, it often leads to unmet expectations and dissatisfied clients. This is particularly common in programs with boreholes below 500 m (1640 ft), where the expectation is to save costs.
The client should seek an evaluation of the actual benefit of the service, not just its feasibility.
What advice would you give to people commissioning directional drilling services?
Grigor Topev: Directional drilling in the exploration industry is far from perfect. It is a complex process in which there are almost always difficulties—with the direction, with the intensity, with the equipment, with the conditions, with the people.
My advice to geologists planning such programs is to keep it simple. The more demanding and complex a directional program is, the higher the risk of issues. It’s as simple as that. Complex trajectories can be achieved, but the real question is: at what cost, with what risk, and with how many unnecessary complications? In many cases, it is far more effective to drill additional mother holes and reduce the volume of directional drilling than to pursue overambitious programs that end up costing everyone more.
As for drilling contractors, they need to understand that directional drilling will inevitably become part of their operations. It must be approached with openness and understanding. If directional drilling is required on a project, it simply means that their conventional methods are not sufficient to execute it. Contractors who recognize this and support directional operations—not only in attitude but also through more favorable rates during such activities—will be preferred by clients.
In the end, it is not just about the total number of drilled meters, but about the amount of effective (pay) meters delivered. Clients should start clearly defining which type of meters they are actually targeting.
Share your thoughts on the future of directional drilling.
Grigor Topev: The future lies in equipment that drilling crews can operate themselves, combined with remote support from directional drilling experts. The reason is obvious: sending specialists to site is expensive, burdensome, and logistically difficult. No one likes it. However, directional drilling is by no means a simple task, and without the necessary technical understanding and problem-solving ability, it simply won’t work. So, this is the challenge the industry needs to address.
Companies that offer a variety of directional equipment and flexible service models will be in the highest demand.
What about the future of diamond drilling from a technological point of view?
Grigor Topev: The reality is that, after so many years, the industry can hardly point to any fundamental breakthroughs. The original Boart Longyear concept from 1958 remains largely unchanged. The other major step forward was the transition from mechanical to hydraulic rigs—again, many years ago.
Since then, what we have seen are mostly small refinements and incremental improvements—faster head assemblies, new rod thread designs, and many ineffective rod manipulators—but no real technological leap. To me, that is highly unsatisfactory and even disappointing. It feels as if the industry is standing still.
It is somewhat surprising that the leading manufacturers in the industry, despite their large engineering teams and resources, are producing less and less meaningful innovation. In my view, they are often disconnected from the real problems in the field and tend to focus in the wrong directions. Meanwhile, smaller companies, driven by motivation, urgency, and a real desire to improve, often come up with more interesting and practical solutions, and in many cases show greater potential to push the industry forward.
In this vein, what are the main challenges in the industry that need to be resolved?
Grigor Topev: Recently, much of the industry’s focus has shifted toward safety. While fully justified, there is also a need to focus on technological improvements that address current challenges and improve productivity, particularly in the following areas:
Reduction of tripping operations. Instead of focusing only on making them safer through rod manipulators, we should also focus on reducing their frequency. Fewer trips mean less wear, lower risk, and less lost time. Drill bit–related issues (wear, polishing, overheating, or damage) remain among the most common reasons for pulling out of the hole. The focus should shift toward wireline-retrievable bits and near-bit sensors.
Unstable ground and problematic zones. These cause significant delays. The current approaches: muds, casing, cementing, rod grease, or simply closing our eyes and hoping the hole will be finished, are often ineffective. The problem is somehow accepted as part of the game, but that should not be an excuse for not seeking real solutions. There are many claims, especially from mud companies, but the reality is far less convincing. Casing is not always feasible, and cementing these zones has a very low success rate. Efforts should be directed toward solutions such as expandable casing systems and fast-setting mixtures pumped through the core barrel, aimed at stabilizing zones quickly and effectively.
Natural deviation is a major source of missed targets, wasted time, and unnecessary cost. The industry still lacks accessible and widely used algorithms for analyzing and predicting it, and more importantly, practical solutions available when needed. It is rare to see wedges or other corrective tools on site unless they were planned in advance. Not to mention that even simple tools like a hex barrel and a longer reaming shell—standard equipment—are often not used.
It’s ironic that every program invests in survey tools that show how much the hole has deviated, but nothing in tools that can actually correct it. And while I may be biased, it’s simply the reality.
What is the biggest issue with workforce in the drilling industry today, and how can it be improved?
Grigor Topev: For decades, the industry has relied on a system where drillers naturally emerge from the more capable helpers. This worked well in the past, but today it is becoming inefficient, unreliable, and a clear limiting factor. Helpers are often hired on a random basis—almost anyone willing to work can get the job. Only a small percentage stay in the industry, and from those, an even smaller percentage are actually suited to become drillers. The whole approach depends too much on chance. Not to mention that helpers are often promoted out of necessity rather than readiness, simply due to increasing workload and lack of prepared staff. We all know the result.
Drilling contractors need a more structured approach. Companies should actively select people with the potential to become drillers, train them properly, and develop them step by step, from helper to driller, through a controlled and intentional process. Formal training before entering the site should not be optional—it should become the standard.
At the same time, experienced helpers should be valued and retained. Their role is critical for safety, efficiency, and overall performance. The difference between a team with a strong helper and one without is immediate and significant.
Another major issue is the lack of proper training programs. Too often, new helpers are brought directly to site and expected to learn on the job, usually from the driller. But a driller is not a trainer, and this approach leads to gaps in both safety and performance. It is not uncommon to see new helpers in their first days struggling with basic tasks, simply because no one has properly explained to them what they should be doing.
In short, improving the level of the industry starts with improving the way people are selected, trained, and developed.
How do you see the current state of collaboration within the drilling industry?
Grigor Topev: Collaboration on the global scale is something that has been missing for a long time. At the moment, the exploration drilling industry does not have a strong, unified voice at a global level. As a result, the interests of drilling contractors are often not properly represented or protected.
We clearly see how mining and exploration companies, naturally driven by their own interests, are able to push pricing and conditions to their advantage. This leads to increasing pressure on drilling contractors, often forcing them into aggressive competition, lowering prices, and working under less favorable terms. In many cases, multiple contractors are placed on the same project, which further intensifies competition and drives margins down.
Without coordination, companies start competing against each other in ways that weaken the entire industry. Instead of collaboration, we see fragmentation, tension, and unnecessary rivalry.
A global organization could help balance this.
Drilling is a job that involves a lot of travel. What are your thoughts about it?
Grigor Topev: Travel is a huge part of our profession, and you either learn to live with it or you’re not cut out for this job. At first, traveling seems romantic, new countries, new people, new sites, a sense of splendor and freedom. And that is indeed part of the truth. Drilling takes you to places a regular tourist would never set foot in, and it gives you access to a world most people don’t even know exists.
But the other side of the coin is that constant travel is no walk in the park. Working outdoors is not always fun. Working 12-hour shifts at 35°C or −35°C (95°F to -31°F) is no joke. High-altitude projects, deep underground operations, jungles, deserts, remote camps. You’re constantly on the go—airports, camps, rig sites—across different time zones, far from the normal rhythm of life and from your loved ones.
Our profession is not an ordinary one, and if you want an interesting, dynamic, and well-paid job, you can’t expect it to be easy, comfortable, and without compromises.
What do you do when you are home?
Grigor Topev: I’m a passionate cook. I’ve been cooking regularly since I was 18. Balkan cuisine is incredibly diverse, and I recommend it to anyone who loves trying new and different things. When it comes to international cuisine, I enjoy making Neapolitan pizza and dishes I’ve picked up during my travels… My favorite cuisines are Japanese, Brazilian, Mexican, Peruvian, and Colombian. I dare say that if I were to open a fine-dining restaurant, it would most likely be very successful, but fortunately, I have no desire to do so. I’m also very passionate about good coffee and craft brews. When it comes to sports, I enjoy skiing with my kids.
For more information: Get in touch with Grigor on LinkedIn
