Content

In the late 1980s, the systematic investigation of metal deposits in Slovenia stopped. Since then, new and more precise analytical techniques have been developed, knowledge of the geology and metallogeny of the area has improved and the use of mineral resources that were previously of little interest has increased significantly. An additional impetus for the resumption of modern systematic exploration of mineral deposits, especially critical ones, is provided by the EU Commission’s CRM Act from 2024. 

The Antimony project focused on the antimony deposits in the area of Trojane. The potential of antimony, a critical raw material for the EU, is very high in the Sava Fold region. Only limited and incomplete data is available on the mines where mining was carried out at the beginning of the 20th century. In particular, there is a lack of knowledge about the exact location, geometry and quality of the veins – all tunels were inaccessible shortly after the end of mining activity and not a single exploration borehole was drilled in the area. The ore bodies need to be investigated using modern research methods in order to reassess the prospectivity of the ore deposit. With the Antimony project, the Geological Survey of Slovenia is following modern trends in the exploration of mineral deposits in Europe and is thus forming a team that could also take on potential future research tasks in this field.

As part of the antimony project, a pilot study was carried out on the area of the antimony ore deposit between Trojane and Znojile. This includes:

• Review of archive data

• Review of the terrain and old mining works

• Application of a portable XRF to detect antimony anomalies on outcrops and cuttings

• Soil sampling at the contact with the parent material using a hand auger

• Analysis of samples using  modern analytical methods with near-total digestion

• Test and application of geophysical methods (GPR and ERT) for the detection of ore bodies

The final outcome of the research will be the development of a program for further antimony exploration, with a proposal for locations for exploration boreholes.

Project phases and their implementation 

1. Review of results of previous research in the study area and new findings in the world in connection with antimony mineralization – completed 

2. Digital capture of the geological map at a scale of 1 : 5000, which was made in 1982 by Ivan Mlakar and colleagues – completed

3. Site inspection  and analysis of selected outcrops by XRF – completed

4.  Implementation of geochemical and other laboratory investigations – completed

5. Geophysical investigation – GRP and ERT – in progress

6. Analysis of results, development of a program of further research with an emphasis on the selection of proposed locations for exploratory drilling – in progress