Paper contribution

Rock Mechanics Aspects of Debar Crystal Cave – Macedonian Wonder of Nature

Milorad Jovanovski; Igor Pesevski; Todorka Samardzioska; Milica Jovanoska Mitreska; Sead Abazi; Filip Kasapovski; Todor Delovski; Velimir Petrovski

Proceedings
EUROCK 2026
Pages
873-882
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The article is dedicated to the Macedonian gypsum crystal cave, located near city of Debar. This is one of the few caves of this kind in the world that contain the unique selenite crystal. It is the most interesting cave, beside the one in Mexico. The cave has a status of nature geological wonder, spaced in a unique geological environment with presence of active faults and hot thermal springs nearby. Its entrance is only few meters above the artificial Debar Lake. It is currently under concession to the company Knauf. Despite the fact that it was first discovered by the Romans more than 2200 years ago and it is part of the largest gypsum quarry in the Balkans, the aspects of rock mechanics have not been presented to the wider scientific community. This is very important, having in mind that the underground openings are very large, without any kind of support, which is a challenge from stability and safety point of view, since sightseeing visits for groups of tourists are arranged from time to time. From touristic and cultural heritage aspect, there are ideas to establish a cultural centre and concert hall in the cave. Therefore, security and rock stability are very important. The paper presents data about properties of the intact rock, rock mass, as well as thermal and acoustic properties of the cave. Results from some analyses are prepared to have an insight into the overall stability of the underground openings. Photogrammetry and LiDAR were combined to produce accurate 3D cave models, enabling detailed mapping and reliable stability assessments. Results from thermal camera surveys, acoustic measurements and ambient temperature and humidity measurements are also presented. The broader targets of the article also include a look how to upgrade the cultural-technological dimension of the cave and its tourist promotion.

Contributors

Authors

  1. Milorad Jovanovski University Ss. Cyril and Methodius, Faculty of Civil Engineering, MKD ORCID 0000-0002-6261-3721
  2. Igor Pesevski University Ss. Cyril and Methodius, Faculty of Civil Engineering, MKD ORCID 0000-0002-2748-5795
  3. Todorka Samardzioska University Ss. Cyril and Methodius, Faculty of Civil Engineering, MKD
  4. Milica Jovanoska Mitreska University Ss. Cyril and Methodius, Faculty of Civil Engineering, MKD
  5. Sead Abazi University Ss. Cyril and Methodius, Faculty of Civil Engineering, MKD ORCID 0000-0001-8263-600X
  6. Filip Kasapovski University Ss. Cyril and Methodius, Faculty of Civil Engineering, MKD
  7. Todor Delovski KNAUF dooel Skopje
  8. Velimir Petrovski KNAUF dooel Skopje

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References

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