Ján Štubňa

Ján Štubňa is a geologist and gemologist affiliated with the Department of Geography, Geoinformatics, and Regional Development at the University of Konstantin Filozof in Nitra, Slovakia. He specializes in the analysis of gemstones, and his recent work has focused on the unique gold ring discovered at the Pustý hrad, which features a rare natural sapphire from Sri Lanka. His research has shed light on the gemstone's authenticity and historical significance, contributing to our understanding of trade routes and cultural influences in the region.