Aligning Croatia’s national solid mineral resources classification system with UNFC: a methodological framework and case-based implications
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Abstract
Reliable and up-to-date information on mineral resources is an essential foundation for strategic decision-making and long-term mining project planning. In Croatia, solid mineral resources have traditionally been classified using the national ABC1 system, which is not aligned with internationally recognised reporting frameworks. This study applies the United Nations Framework Classification for Resources (UNFC) to a representative group of Croatian exploitation fields. In the national regulatory context, this term refers to a formally defined project category used by the mining authority to describe the legal and operational status of the mining project. The analysed group includes active and non-active exploitation fields, historic exploitation fields, and examples characterised by temporary administrative irregularities, defined as situations in which mining activities continue under acquired rights, rather than under an active concession. Two complementary approaches were used: the ORAMA (2019) PROJECT (2019) decision-flow methodology and the direct application of the UNFC Guidance Europe (UNECE, 2022). Independent assessments on the non-active exploitation fields conducted by two experts, resulted in fully aligned UNFC classifications despite differences in analytical emphasis. This outcome demonstrates the reproducibility and robustness of the UNFC framework. An additional example illustrates the dynamic nature of the UNFC by showing how temporary changes in project status can influence the project maturity and assigned category. The results confirm that the UNFC provides a transparent, adaptable and harmonised framework suitable for integrating Croatian mineral resource data into national and European reporting systems. Rather than replacing the national system, this study demonstrates a practical and transparent pathway for UNFC implementation and interoperability with wider relevance beyond the Croatian context.
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References
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