Mineral Rebirth – Interview to Umberto Gioia, Managing Director in Mineraria Gerrei

The production recovery of the Silius mine marks a turning point for the fluorspar industry in Europe. Umberto Gioia , Managing Director in Mineraria Gerrei, was interviewed by Alice Magon and explained how the ambitious revamping plan is developing and what our strategic vision is.

In the Silius mine, located to the east of the province, there is one of the most important fluorite deposits of Europe. After 18 years of inactivity, the historic mine was able to find new life thanks to economic commitment and technologies implemented by Mineraria Gerrei, a young but ambitious company that has taken on the burden of relaunching its production. Fluorspar is a mineral essential for the production of hydrofluoric acid and other compounds used in numerous industrial sectors. By virtue of this widespread use, it is becoming increasingly relevant in a geopolitical context that places critical raw materials at the center of attention, determining final prices of numerous products, including key components of construction machinery and equipment.

The European Union recently introduced the Critical Raw Materials Act (CRMA), a strategic plan aimed at reducing dependence on imports of essential raw materials for green technologies and for industry. In this context, fluorspar is considered a critical raw material, given its industrial relevance and the limited availability on the global market. In this scenario, the Silius mine, thanks to its position and to the new extraction technologies adopted, represents a fundamental piece in the European reshoring strategy and diversification of sources.

The global fluorspar supply situation, dominated by a few producers such as China, Mexico and South Africa, led to an increase in demand and prices. With an expected annual production of approximately 70,000 tons of pure fluorspar over 97% and a focused approach to the circular economy, Mineraria Gerrei aims to contribute to reducing Europe’s dependence on imports and security of supply.

What were the main interventions and investments planned for the relaunch of the Silius mine?

We faced a complex revamping process, which involved numerous structural and technological aspects of the mine. First, we focused on replacing the existing shafts’ lifting equipment and on the realization of a new extraction shaft, a very complex structure up to 600 m deep under construction by partner company Edilmac through raise boring methodology. We then started construction of a fully new treatment plant located at the mine site to ensure optimal process efficiency. This intervention, together with the refurbishment of many other installations (buildings, workshops, machinery, ventilation and electrical systems, etc.) represents an overall investment of approximately 50 million euros.

Was the decision to restore this mine influenced by the dynamics of the fluorspar market?

Certainly. Our experience in the sector has allowed us to perceive in advance a change in the dynamics of the market. Although in the 2000s the prices were extremely low, starting from 2015-2016 we observed a strongly increased demand for fluorspar, driven by the downstream chain of high-tech technologies, such as batteries, superconductors and fluoropolymers. The global production remained virtually stable for over two decades, given the difficulty of opening new mines and the long development time required. Silius, compared to a new mine, had some important advantages, consisting of an existing underground tunnels infrastructure and a set of already investigated ore panels ready to be exploited. However, we had to go through a long authorization and technological rehab process, which took us eleven years to get to this point.

You mentioned a growing demand for fluorspar in Europe. What is the current situation and how it fits the Silius mine in this context?

Europe is one of the largest consumers of fluorspar, accounting for approximately one third of world consumption. However, the internal production is extremely limited: the few active mines currently cover just 6% of the continent’s needs. Even with the entry into production of the Silius mine and another project starting in Germany, we will only be able to satisfy 11-12% of European demand. This imbalance makes Europe heavily dependent on imports from countries such as Mexico and South Africa, resulting in high transportation costs and security risks of supply.

What are the advantages of having a production source within Europe?

Having a European production source is essential for many reasons. First of all, reduces dependence on imports, ensuring greater stability prices and continuity of supplies. Furthermore, geographical proximity leads to a significant reduction in transportation costs, which is a crucial factor considering the distance between Europe and main producing countries, such as Mexico and South Africa. Finally, in a political and economic context like the current one, with increasingly customs restrictions and stringent environmental regulations, having domestic production offers an important strategic advantage.

I ask you the question that surely all readers are waiting to read. When is the official opening of the Silius mine scheduled? Regarding the exploitation methodology, moreover, can you briefly describe what will be adopted for the Silius mine?

Our goal is to start production in 2026. We are working hard to meet this deadline and we are confident that we will be able to enter into full swing within the established timeline. The ore exploitation method we want to adopt is an upwards sub level stoping with backfilling, widely tested in Silius in the +70 years history of mine. Such a method guarantees high productivity maintaining excellent levels of security both during the development phase and at the end of exploitation, thanks to voids stabilization through backfilling. The method involves the need for a head tunnel and a base tunnel along the ore vein direction, followed by the opening of vertical slots and intermediate sublevels to outline the ore panel contour. Downwards long hole vertical drilling from upper sublevel is the last preparation before the use of explosives. Mucking with loaders from the lower sublevel to the nearest vertical ore pass is the last step before automatic loading and transport process to the surface.

Sustainability has become an element crucial in the extractive industry. Which are the solutions adopted to reduce the environmental impact of the operations?

Our approach to mine management is based on the principles of circular economy and on a strong focus on environmental sustainability. The beneficiation plant, for instance, is designed to operate in a closed loop, hugely reducing water consumption compared to the past; furthermore, we won’t need anymore tailings disposal facilities over the ground, since any by-product of the beneficiation process will be used for backfilling. This approach allows us to minimize the environmental impact and to fully comply with European regulations.

Which technical approach did you adopt in the selection of mining machinery?

One of the main problems we faced is related to the small size of our tunnels, both by height (generally about 3-3.20 meters) and by turning radius of ramps and intersections. This forced us to look for compact equipment, obviously compliant with EU Directives in terms of CE certifications and Stage V standard emissions, however suitable for power and capacity to the production needs of the mine. Unfortunately, major manufacturers of underground machinery developed up-to-date solutions just for larger extra EU markets, featuring lower technical and environmental standards and much bigger tunnel sizes, not applicable to our case. These limitations also apply to full electric vehicles, which we mean to adopt as soon as possible also in Silius, but which are still unavailable for narrow vein mining sites. As a result, just a handful of machinery producers have been selected.

Anyway, we can count on a fleet, among operating and ordered machines, wide enough to start production and a proper evaluation of the additional vehicles expected in the first years of operation. Specifically, we will be able to count on around 35 vehicles, including jumbos, production drills, bolters, loaders, dumpers, multi-purpose vehicles such as mini excavators and MEWPs, trains, electric vehicles for the transport of personnel.

Which structural improvements were necessary to reach mine compliancy to modern standards?

We had to undertake a relevant work to bring installations up to date, dealing, for example, with harmonization of electrical voltages, with new HSE regulation compliancy, with replacement or refurbishment of shafts’ lifting equipment, with rehabilitation of mine facilities such as offices, workshops, laboratories and access roads, in order to ensure a safe and modern workplace.