## 1 Introduction  
Minerals are essential for sustaining the economic development of our society, and the increase in the world population in recent years has sparked a renewed interest in mineral exploration. In 1964, the Southern Mining Industries (joint stock company) of Naples explored an area in the Molino Masticraro locality, along the Fiumarella stream, northwest of Catanzaro (Calabria, Southern Italy), to assess the existing outcrops for mineral exploitation. Geological investigations led to the discovery of a 1 to 3 m-thick deposit consisting of barite veins running mainly along the porphyry-granite contact [1]. Secondary minerals with low concentrations of fluorite, galena, pyrite, chalcopyrite, and sphalerite were also found [1; 2; 3; 4]. Once prospecting ended in 1967, the \"Masticraro Barite Mine\" mining concession was issued to the Southern Mining Industry company: barite exploitation began in 1968-1969, with an average production of about 80,000 tons per year [1]. Extraction initially took place using the \"cut in direction\" method, which proved unsafe for processing and resulted in medium productivity due to the geological setting of the barite veins; the subsequent adoption of the \"room and pillar\" method greatly improved both productivity and safety in the workplace. The extracted mineral, with a good degree of whiteness, was used prevalently in the paint industry and, secondarily, as an additive in oil drilling [2]. In 1980, the Southern Mining Industry renounced the concession because the exploitation of the area was no longer economically viable. At the end of the exploitation activities, work was carried out to ensure the safety of the site, including the construction of concrete diaphragm walls to stabilize the entrances and prevent access to the tunnels [2]. In the Masticarro Barite Mine, minerals such as connellite, linarite, and wulfenite were recently detected, in addition to primary minerals such as barite and galena [5; 6]. This makes the Masticarro Barite Mine particularly interesting not only for its naturalistic value, but also for its economic potential. In recent years, the European Union has assigned great importance to securing mineral resources for industry, as there are some 30 million jobs depending on the availability of raw minerals that are in great demand for strategic sectors such as renewable energy. Note that barite is present in the EU's list of critical raw minerals [7], and EU policies and the UNESCO strongly encourage its identification, characterization, and subsequent mining. Currently, most of the mines and quarries in the Calabria region are dismissed and testify to a grand monument of the Calabrian industrial archaeology. Nowadays, the study of the Masticarro Barite Mine represents a great challenge for the use of available mineral resources. Therefore, the detailed knowledge of minerals from the Masticarro Barite Mine may also tackle the urgency of mineral availability and supply. This study aims to fully characterize new minerals detected for the first time in the Masticarro Barite Mine: anglesite, cerussite, gypsum, langite, malachite, and posnjakite. Furthermore, the aim of this study is to explore in detail the mineral characteristics by multi-analytical investigations to understand the relationships between the mineralogical and physicochemical properties. Samples were identified and characterized through optical microscopy (OM), micro-Raman spectroscopy (\(\upmu\)-R), and scanning electron microscopy, combined with energy dispersive spectrometry (SEM/EDS). In particular, micro-Raman spectroscopy allowed us to identify and characterize minerals through rapid, non-destructive, and economic analyses, as demonstrated by its successful use in numerous studies [8; 9; 10; 11; 12]. New Raman bands were identified for langite, malachite, and posnjakite.