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Nowadays there is a great number of recovery initiatives of abandoned mining sites in a belt that runs from the Eastern Alps through Liguria, Emilia-Romagna up to Tuscany in Italy and in cross-boundary areas. This study involves their census and their characterization focusing on mineral deposits geology aspects. During the last decade we have seen an increasing interest in these initiatives by the Scientific Community, by the Government (ISPRA) and Territorial Bodies (Tuscany and Lombardy). In the 1980s and 1990s the closing of the majority of the Italian mines, most of which metalliferous, carried out to a sensible reduction in Italy in the scientific production on the ore deposits geology. Forty-five improvement initiatives of mining sites (ore and industrial minerals mines and ornamental stone quarries) have been identified. For each site a monographic paper has been produced after direct surveys in situ. A critical comparison between what is offered and what is really accessible by users has also been realized. The data synthesis yielded a thematic map of the situation of the recovery and improvement initiatives of abandoned mining sites from the Alps to Tuscany updated to 2010. The recovery initiatives have been divided in three categories which include “Mines and Quarries”, “Parks and Museums”, “Projects”. The first group enables visitors to see the ore deposit with their own eyes, as it proposes to people a visit of underground mining stopes and levels; the second group offers external paths and/or museum exhibitions, sometimes with artificial reconstructions of mining tunnels; at last the third group is made up of the initiatives at a stage of feasibility study. From this study it appears that at present the Italian regions with the largest number of recovery initiatives are Trentino – Alto Adige, Lombardy and Tuscany. Most of these sites involve ore deposits, mainly base metals sulphides; deposits of industrial minerals, indeed, are incompletely represented by talc, fluorite, salt, sulphur and coal mining sites; a remaining small part is made up of ornamental stones quarries, all underground. From the Alps to Tuscany today it is possible to have a recovered mining heritage that potentially enables to carry out live observations on mineral deposits geology topics about the following important categories of deposits: - polymetallic and talc deposits (stratiform and vein-type) in the Crystalline Basements; - iron, lead – zinc (Ag, Cu) “MVT or carbonate-hosted”, coal, salt, and sulphur stratiform deposits in the Mesozoic and Tertiary sedimentary cover; - polymetallic vein-type pyrite, gold and talc deposits; - Sed-Ex type copper, pyrite and manganese deposits in the alpine and appenninic ophiolites and meta-ophiolites and in their covers; - polymetallic skarn type deposits connected to Tertiary plutonism; - gold-bearing placer deposits in Quaternary fluvioglacial sediments; - ornamental stones quarries (marbles) in the Paleozoic (Alps) and in the Mesozoic (Appennines). All the recovered mining sites are different for types and settings of deposits, mineral substance, geological domain, metallogenic context and age and they are present in a defined geographic neighborhood: from the Alps to Tuscany. The in situ surveys have pointed out that the mineral deposits geology basic elements of these recovery initiatives are often incomplete or lacking, while great emphasis is given to historic information, together with mining industrial archeology. This heritage, indeed, covers not only industrial archaeology and/or tourism topics, but also important geological and mineral deposits aspects. The local geology of mineral deposits is indispensable condition for the opening of quarries and mines. Therefore it is also necessary to pass to the wide public this important cultural aspect. Besides this heritage would be available to the scientific community and to Italian and transalpine universities for didactic and cultural aims.

Un orizzonte di calcari, in parte dolomitici, con intercalazioni bituminose e inquarzamenti massivi, di età Ladinico-Carnica, è ben noto nella letteratura giacimentologica e soprattutto nella tradizione mineraria lombarda come “Metallifero”. Stratigraficamente confinato al passaggio tra una potente sequenza di calcari di piattaforma carbonatica a letto e una sequenza lagunare a dominante silico – clastica a tetto, si estende per circa 80 km in senso O-E, dal Lago di Lecco alla Val Sabbia. Questo livello ospita frequenti corpi minerari a Pb–Zn–F–Ba che, nell’ultimo millennio, hanno dato luogo ad estese ed intensive coltivazioni minerarie. Il bacino estrattivo più noto è quello di Gorno (l.s.) in Val Seriana (BG), dove sono stati estratti complessivamente non meno di 10 Mt di grezzi a blenda, galena e calamine. Sono presenti anche numerosi poli estrattivi minori dove, proprio per la particolare connotazione giacimentologica dell’evento metallogenico (depositi strata-bound con zonalità laterali), si alternano miniere di sole calamine, o di solfuri metallici, oppure esclusivamente di fluorite o di barite. In questi siti minerari non si esercita oggi alcuna attività estrattiva. I corpi minerari sono irregolari e variabili: come loro distribuzione all’interno del Metallifero, come morfologia, giacitura e dimensioni. Ne è conseguita una altrettanto varia tipologia di tecniche di coltivazione mineraria. Infatti le società che si sono succedute almeno negli ultimi due secoli hanno adottato sistemi di coltivazione mineraria tra i più disparati, nel tempo e nelle aree di rispettiva competenza, per livello tecnologico, scelte progettuali, estensione delle concessioni ed entità degli investimenti. I lavori minerari, in superficie e in sottosuolo, sul territorio interessato da questo orizzonte “Metallifero” consentono di disporre di un immenso patrimonio di valenze geologiche, giacimentologiche e tecnologiche di archeologia industriale. Gallerie, che si diramano per qualche centinaio di km da quote fondo valle fino a oltre 2000 m, permettono di osservare aspetti mineralogici, litologici, stratigrafici, strutturali e soprattutto giacimentologici, come alcuni vuoti di coltivazione, sotto una luce particolarmente inusuale e suggestiva, quasi una rappresentazione 3D dal vivo. Ciò che resta degli impianti di trasporto e di trattamento del minerale, come teleferiche, decauville, discariche e laverie, non rappresentano solo un complesso di strutture minerarie degradate da bonificare, ma possiedono valenze ben superiori: esse testimoniano che l’attività estrattiva ha fortemente marcato queste località, andando a costituire nei secoli una inconfondibile fisionomia di “paesaggio minerario”. Il “Metallifero”, dipanandosi attraverso e legando tra loro alcune vallate delle Alpi Lombarde, rappresenta una sorta di filo conduttore di un ideale percorso, allo stesso tempo geologico e di archeologia industriale, storico-culturale ma anche turistico. L’in- 65 sieme delle sue valenze, coniugate in un mosaico armonico, lo pone come un “unicum” che richiede una sua valorizzazione necessariamente unitaria e complessiva, potendosi a pieno titolo denominare “Via del piombo e zinco delle Orobie”. In fase progettuale sono da ricercare quindi offerte diversificate per una ampia gamma di potenziali fruitori. Gli strumenti idonei potrebbero essere una sorta di “Itinerari Turistici Integrati” (ITI), pensati e progettati in modo da permettere al potenziale fruitore di calarsi nei molteplici aspetti, tecnologici, naturali e sociali, che hanno contribuito a creare la personalità di queste valli. Gli ITI faranno conoscere e vivere sia le esperienze in sottosuolo sia i fenomeni naturali all’aperto e permetteranno al visitatore di arricchirsi culturalmente, mediante ricostruzioni didattiche di soggetti storici, geologici o di tecnica mineraria, o di partecipare in prima persona alle visite tramite metodi interattivi. Attualmente sono in corso iniziative, sia da parte della Regione Lombardia, con il supporto di Università, che da parte di Comuni, singoli o raggruppati in consorzio, per la valorizzazione di alcuni siti minerari e per la messa in sicurezza di aspetti riguardanti la Protezione Civile. Tali iniziative soffrono però della tragica situazione attuale di dispersione di tutta la documentazione tecnica o della sua pratica indisponibilità. A tal riguardo si ritiene quindi indispensabile un investimento, anche istituzionale, oggi ancora possibile grazie alla memoria storica di tecnici e ricercatori che, in passato, si trovarono ad operare personalmente nelle miniere ancora in attività. Sarebbe fortemente auspicabile inoltre che i progetti di recupero in atto e futuri su queste miniere rispettino la continuità e unitarietà del tema geo-giacimentologico del “Metallifero” e non siano improntati a privilegiare iniziative troppo locali, se non campanilistiche, e talora aspetti più ludici che culturali. Abstract - A horizon of partly dolomitic limestones, with bituminous intercalations and quartziferous bodies, Ladinian-Carnian in age, is well known in geological literature and Lombard mining tradition as “Metalliferous”. It is stratigraphically confined between a thick sequence of carbonatic platform limestones at the bottom and a siliciclastic lagoon sequence at the top; it extends about 80 km, in an W-E direction, from the Lecco Lake to the Sabbia valley. This horizon hosts several Zn-Pb-F-Ba ore bodies, extensively mined during the last millennium. Gorno is the most important mining field of the Seriana Valley (BG), where about 10 m. raw sphalerite, galena and calamine ores were extracted. There are a lot of minor mining sites as well located where the peculiar type of metallogenic event (strata-bound ore deposits with lateral zoning) produced alternations of calamine ore deposits, or metal sulphides, or exclusively fluorite – or barite – like the Laghetto di Polzone and Cespedosio mines. Today these mining sites are abandoned. The ore bodies have an inhomogeneous distribution inside the “Metalliferous”, and are irregular in shape (lenticular, columnar or stratiform), attitude (from sub-horizontal to sub-vertical) and size (length ranging from 100 m to more than 1 km, thickness from few meters to more than 10 meters). As a consequence, the mining exploitation techniques are varied, and the companies that mined during the last 2 centuries have used different techniques, depending 66 on technology, planning, extension of the mining concession and investments. These mining activities, both at the surface and underground, represent a huge heritage of ore geology and industrial archaeology. Hundreds of kilometres of tunnels – from the valley floor to more than 2000 meters in height – allow detailed mineralogical, lithological, stratigraphical and structural observations (i.e. imposing mining stopes), as a live, evocative 3D representation. The remnants of the ore conveyance and processing plants – like cableways, decauvilles, dumps and washing plants – are not only decayed mining plants to reclaim, but in fact they have a much bigger value: they testify that the mining activities marked this area, moulding in the centuries an unmistakable “mining landscape”. Briefly the “Metalliferous”, winding and binding some valleys of the Lombard Alps, is like a thread of an ideal geological, industrial, historical and tourist route (some mining districts lie inside a Regional Park). These values combined as a whole, make the “Metalliferous” as a “unicum”, requiring comprehensive improvement, because it deserves the qualification of “The Orobic Pb and Zn Route”. During the planning stage it is essential to contemplate different proposals for a wide consumer range (from school-children to universities). The appropriate tools could be a sort of “Supplemented Tourist Routes” (STR), planned for the peculiar technological, natural and social requirements for the different consumers. The STR will be able to create a revival of underground experiences (the suggestion of the darkness and the ore mineral) and open air phenomena (geology, flora, fauna and landscape). The STR will allow cultural enrichment of visitors, through didactic reconstructions of historical, geological or technical aspects, or by guided mineral search and collection. Currently time, there are some initiatives managed and supported by the Lombardy Region and by the municipalities, universities and authorities, in order to improve and to make safe some mining sites. Nevertheless, all these initiatives are penalised by the dispersion or unavailability of the technical documents and records. For this reason, an investment for the recovery of these documents is essential and still possible, thanks to the historical memory of technicians and researchers that worked in the old mines, in order to commence effective recovery projects, without favouring only local or light-hearted aspects.

GUIDING LINES FOR THE IMPROVEMENT OF THE TRIASSIC METALLIFEROUS MINING HERITAGE IN LOMBARDY. A few tens of meters thick horizon of partly dolomitic limestones, with bituminous intercalations and quartziferous bodies, Ladinian-Carnian in age, is well known in geological literature and Lombard mining tradition as “Metalliferous”. It is stratigraphically confined between a thick sequence of carbonatic platform limestones at the footwall and a siliciclastic lagoon sequence at the hanging wall; it’s extension reaches about 80 km, striking W-E, from the Lecco Lake to the Sabbia valley. This horizon hosts several Zn-Pb-F-Ba ore bodies, extensively mined during the last millennium. Gorno is the most important mining field of the Seriana valley (BG), where about 10 Mt raw sphalerite, galena and calamine ores were extracted. There are a lot of minor mining sites as well, located where the peculiar type of metallogenic event (strata-bound ore deposits with lateral zoning) produced alternations of calamine ore deposits, or metal sulphides, or exclusively fluorite – or barite – like the Laghetto di Polzone and Cespedosio mines. Today these mining sites are abandoned. The orebodies have a inhomogeneous distribution inside the “Metalliferous”, and are irregular in shape (lenticular, columnar or stratiform), attitude (from sub-horizontal to sub-vertical) and size (elongation ranging from 100 m to more than 1 km, thickness from few m to more than 10 m). As a consequence, the mining exploitation techniques varied as well, and the companies that mined during the last 2 centuries made use of dissimilar techniques, depending on technology, planning, extension of the mining concession and investments. These mining activities placed, both at the surface and underground, represent a huge heritage of ore geology and industrial archaeology. Hundreds of km of galleries – from the valley floor to more than 2000 m in height – allow detailed mineralogical, lithological, stratigraphical and structural observations (i.e. imposing mining stopes), as a live, suggesting 3D representation. The remnants of the ore conveyance and processing plants – like cableways, decauvilles, dumps and washing plants – aren’t only decayed mining plants to reclaim, but in fact they have a much bigger value: they testify that the mining activities marked this area, moulding in the centuries a unmistakable “mining landscape”. Briefly the “Metalliferous”, winding and binding some valleys of the Lombard Alps, is like a thread of an ideal geological, industrial, historical and tourist route (some mining districts lie inside a Regional Park). These values combined as a whole, make the “Metalliferous” as a “unicum”, requiring comprehensive improvement, because it deserves the qualification of “The Orobic Pb and Zn Route”. During the planning stage it’s essential to contemplate different proposals for a wide consumer range (from school-children to universities). The appropriate tools could be a sort of “Supplemented Tourist Routes” (STR), planned for the peculiar technological, natural and social requirements of the different consumers. The STR will be able to create a revival both of underground experiences (the suggestion of the darkness and the ore mineral) and open air phenomena (geology, flora, fauna and landscape). The STR will allow cultural enrichment of visitors, through didactic reconstructions of historical, geological or technical aspects, or by guided mineral search and collection. At present time, there are some initiatives managed and supported both by the Lombardy Region and by communes, universities and authorities, in order to improve and to make safe some mining sites. Nevertheless, all these initiatives lack in the tragic dispersion and unavailability of the technical documents and records, and at the same times they favour more ludic or parochially-minded aspects. For this reason, a investment for the recovery of these documents is essential and still possible, thanks to the historical memory of technicians and researchers that worked in the old mines.

Between the sixties and the eighties, several mines and quarries in Lombardy (northern Italy) stopped production, almost never for exhaustion of reserves, and often the mining activities were completely abandoned. Some of these ore and stone deposits were exploited since historical age, and they have had an important influence on the social and economic development of the major valleys of Lombardy. Well known is the supply of rocks used in local buildings and monuments, and of raw materials for the birth and the growth of metallurgic and manufacturing industries. On the other hand, the remnants of all these activities have left a great number of environmental impact factors, for example some surface collapses or landslides above and around the stopes, or as local pollution by toxic waste. But at the same time, the ancient mining technologies represent a very important heritage of industrial archaeology. Moreover, the great chance to have a clear underground sight of the rock bodies (like an “internal” 3D sight) represents for several mining sites a wonderful geological heritage. Just by recovering the technological mining heritage and studying the geological setting, we could choose some of these sites, with the aim of starting and testing recovering and improving initiatives, strictly related to their own peculiarity, and in respect of the locally well-established so called “mining landscape”.

The natural stones used on the Romanesque north wall of the St. Martino church in Mendrisio Cavallo Giovanni*, Corredig Guido**, Dell’Oro Davide**, Galimberti Lucia**, Rodeghiero Franco**, Vezzoni Bruno* *University of Applied Sciences of Southern Switzerland, Dept. Environment, Construction and Design, LTS, PO Box 12 CH-6952 Canobbio (Tessin) giovanni.cavallo@supsi.ch ** University of Milan Bicocca, Dept. of Geology, Piazza delle Scienze 4 Milan (Italy) The Romanesque north wall of the St. Martino church in Mendrisio (fig. 1) has been chosen as model for an applied research project called OSMATER (http://istgis.ist.supsi.ch:8001/osmater/) aimed to link the original materials used, the quarries and the possible routes. Irregular scabbled stones of silicified limestones have been largely used for the wall corresponding to the oldest one. This stone is locally called Pietra di Salorino (Salorino stone) being the village part of the mining district. The upper part of the wall is decorated with small arches in Travertine called Tufo Lombardo (Lombard Tuff). The final cornice is in individual decorated blocks of sandstone. The correlation between the microstructure and the composition of the raw materials and the stones used on the wall allows to refer the silicified limestone to the quarry located at Monte Casima close to the Salorino village and the church. The rock belongs to the Moltrasio stone formation (Low and Middle Lias). It is a marly limestone, pale grey in colour, with veins filled up with coarse grains of calcite and nodules of flint. The Quaternary Travertine is locally called Tuff for its analogies with the volcanic rocks. The petrographic examination allows to refer this material to the Travertine deposits located in Rancate, a village close to Mendrisio. The sandstone belongs to the formation Conglomerate of Como (Oligocene); it comes from the quarries located in Malnate and is locally known as Pietra Molera. The colour ranges from grey to greenish, the grain size from medium to fine, the mineral phases are quartz, feldspars, biotite and muscovite. Grains of metamorphic and carbonatic rocks are also present. The matrix is siliceous. The source of the silicified limestones and the travertine is just close to the building. The sandstone quarry is a little bit far from the church. Symposium 8: Building Stones – application, suitability, research

The measurement of the natural radioactivity of 112 ornamental stones has been performed with gamma spectrometry. The rocks, representing the most diffused commercial varieties from Italy and foreign countries, are of magmatic, metamorphic and sedimentary origin. The natural rocks may contain common forming- and accessories minerals (i.e. feldspars or zircon) which have radioisotopes emitting alfa, beta particles and of gamma rays. In the previous works the gamma radioactivity measurements were performed on ground samples of ornamental stones, whereas in this work the rocks are analysed as 15x15 cm wide and 1 to 3 cm thick tiles, to simulate the real use conditions. First of all the samples are screened by means of a NaI(Tl) portable scintillation detector. Three representative samples were tested with HPGe gamma spectrometer using them as standards for the NaI(Tl) gamma spectrometer calibration. The measured gamma radioactivity (in Becquerel) refers both to the specific activity of each radioisotope and to the total activity of the samples. The sedimentary rocks show total activity values between 250 and 500 Bq, always lower than those of magmatic/metamorphic rocks. 40K is the most abundant radionuclide: its specific activity is < 900 Bq. Magmatic rocks have higher total activity than the previous ones; the maximum value is 2190 Bq in an alpine Porphyroid. They contain almost all the radioisotopes detected by NaI(Tl) spectrometer and 40K shows values up to 2000 Bq. The strongly variable values observed in all samples are always comparable with those of other building materials. Gamma spectrometry and scintillation detector data show a good correlation: so the use of scintillation technique could be encouraged in order to perform preliminary information on the ornamental stones radioactivity.

I depositi di minerali utili che sono distribuiti sul territorio delle tre provincie lombarde di Lecco, Bergamo e Brescia e che hanno dato in passato, e localmente danno ancora, luogo ad attività estrattive, possono essere inquadrati, dal punto di vista giacimentologico, in base alla sostanza minerale o metallo per cui sono stati coltivati, alla loro forma e giacitura e in rapporto alla roccia incassante. Partendo dalle unità geologiche più antiche, cioè dalle rocce metamorfiche del Basamento Cristallino Sudalpino, poste nella fascia settentrionale delle tre provincie, nella zona dell’alto Lario furono attivi numerosi cantieri sia per corpi pegmatitici nei micascisti, con feldspato prevalentemente potassico, sia per filoni pegmatitici ad albite e quarzo prevalenti. A partire dal Lago di Como e dalla Valsassina, lungo una fascia prossima al crinale delle Orobie Valtellinesi, decorrente da Ovest fino alla Val Paisco come estremo nord-orientale e più a Sud anche in Val Trompia, furono coltivati intensamente per il ferro, numerosi corpi soprattutto filoniani a siderite prevalente. Di queste mineralizzazioni sorprende, più che la quantità di minerale estratto, la costante ricorrenza entro litologie ben definite del Basamento Cristallino Sudalpino per un’estensione geografica notevole, di circa un centinaio di chilometri, dal Lago di Como alla Val Camonica. Mineralizzazioni filoniane a prevalenti solfuri polimetallici in ganghe quarzoso - sideritiche, ospitate all’interno del Basamento Sudalpino o nell’immediato intorno Basamento – Copertura Permo-Carbonifera, sono state sfruttate in varie località della Lombardia. Esse sono concentrate nella parte centro-orientale, ad esempio argento in Val Seriana, solfuri misti, rame e bismuto in Val Camonica e di nuovo argento in Val Trompia. Localmente questo tipo di corpi può arricchirsi in modo estremo di ganga, soprattutto fluoritica, dando luogo a giacimenti di notevole tonnellaggio, in cui i solfuri metallici e l’argento costituiscono solo sotto-prodotti, come il caso della miniera di fluorite della Torgola-Graticelle in Val Trompia. Nelle potenti sequenze di rocce vulcano – clastiche della copertura carbonifero-permiana, giacenti sopra le rocce metamorfiche del Basamento Sudalpino, troviamo, distribuite dal Varesotto alla Val Seriana e poi in Val Camonica fino alla Val Trompia, una ricca serie di mineralizzazioni per lo più filoniane che sono state intensamente sfruttate, soprattutto nel 20° secolo. Si tratta prevalentemente di corpi ricchi in barite e/o fluorite, anche se sovente venivano recuperate anche discrete quantità di metalli, presenti come solfuri, come Pb, Zn, Ag; talora prevaleva la siderite e in questo caso venivano coltivati per il ferro. E’ verosimile che le faglie in cui sono ospitati questi depositi siano anche espressione di una vivace vulcano-tettonica attiva nel Permiano e che parte delle mineralizzazioni si sia messa in posto già a quell’epoca per fenomeni idrotermali connessi al magmatismo. Un caso a parte è rappresentato dalle mineralizzazioni ad uranio che, presenti soprattutto nelle rocce ignimbritiche permiane della Formazione di Collio in Val Seriana e al contatto tettonico tra queste e il Basamento Cristallino, sono state cubate e tracciate da gallerie di preparazione ma non sono mai state coltivate. Alla base della Serie Triassica, in rapporti di strettissimo legame con una tipica sequenza sedimentaria di arenarie, siltiti e calcari più o meno fossiliferi, nota come formazione del Servino, troviamo mineralizzazioni stratiformi a siderite. Esse, note da tempo, hanno una notevole estensione e continuità laterale in Lombardia. Intensamente sfruttate, a partire da epoche remote fino alla completa chiusura delle miniere negli anni ’60, favorirono sicuramente la nascita e lo sviluppo di un’industria siderurgica e metallurgica locale. Intervallate ai banchi a siderite del Servino sono state coltivate intensamente anche mineralizzazioni filoniane a barite, soprattutto nelle miniere dell’alta Val di Scalve in provincia di Bergamo e nelle vicinanze di Pisogne in provincia di Brescia. Nelle serie carbonatiche triassiche, in corrispondenza del passaggio stratigrafico Ladinico – Carnico, tradizionalmente denominato “Metallifero”, si trovano, dalla provincia di Lecco a quella di Brescia, corpi lenticolari, colonnari e/o stratiformi con minerali di zinco, piombo, fluorite e barite. Molto noto e importante è stato il distretto delle miniere piombo - zincifere di Gorno-Oneta, in Val del Riso. Infine, soprattutto nella fascia montuosa delle tre provincie più vicina alla pianura, alcune formazioni calcareo-marnose del Trias superiore, del Giurassico, del Cretaceo o del Paleogene hanno fornito e forniscono attualmente materia prima per l’industria del cemento, la cosiddetta marna da cemento. Sebbene propriamente non considerabili come materiali di 1° categoria, anche argille per laterizi, dolomia per uso industriale, gesso da cottura, e calcare per calce vengono prodotti in Lombardia.

Tourmaline breccias in the preAlpine basement in Val Trompia (Southern Alps, Northern Italy) are related to late Palaeozoic granites and are associated with Sn-W -bearing ore deposits. The breccias are rich in acicular tourmaline with variable textural and compositional characteristics. At least four stages of tourmaline crystallization are distinguished, mainly by Mg/Fe ratios. All tourmalines can be classified as «alkali group» varieties using recent nomenclature schemes. Compositions vary from schorl-dravite for earlier, main-stage type I and II coarse crystals, to highly Fe-enriched tourmalines, probably approaching the povondraite endmember (typical of oxidized hydrothermal environments), for type Ill and IV fine-grained tourmalines within late veinlets. Whole-rock REE geochemical data show variable, locally remarkable enrichments in LREE related to the action of hydrothermal fluids. Coarse tourmalines occurring in the cryptocrystalline groundmass of the Orobic tourmalinites, which are hosted in cataclastic zones along the tectonic contact between basement and Permian volcanosedimentary cover rocks in the Lake Diavolo area (southern Alps), have schorl-dravite compositions similar to type I and II, main-stage Val Trompia tourmalines. The Orobic tourmalinites were considered of metasomatic origin by previous studies. The Val Trompia tourmalinites can be interpreted as having formed by magmatic-hydrothermal fluids that produced metasomatic tourmalines with different compositions at different distances from the fluid source (magma). Compositional analogies between tourmalinites of the two areas may therefore reflect similarities between the tourmalinization processes that developed in relation to large-scale Permian magmatic-tectonic activity. The Val Trompia tourmalinites thus may represent deeper metasomatic products, closer to the magma chamber, whereas the Orobic tourmalinites would have formed from hydrothermal fluids injected along shallower faults during coeval volcanic activity.