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Упит dcterms_subject_txt:Mineral deposits

306 items

  • A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)

    Jelena Ratković, Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin (2016)
    ... (Fig. 2), these deposits contain alluvial and terrace riverine-lacustrine sediments made up of medium- grain gravels and sandy gravels (river terraces and alluvial plains - riverbed sediments of the Kolubara, the Kladnica, the Turija and the Peštan). There are also other deposits, such as diluvia ...
    ... (2016) and Đinđić et al. (2016). With regard to the topic of this paper, many researchers worldwide have addressed hydrogeologic systems of ore deposits, groundwater flow and processes that affect the hydrogeology of mining sites, including: Dimitrakopoulos et al. 2000; Rapantova et al. 2007; Ka ...

  • Генеза хидротермалног Cu-Au система Чукару Пеки (Источна Србија)

    Милош Велојић (2021)
    Главни циљ испитивања хидротермалног система Чукару Пеки је разумевање процеса који су довели до његовог настанка, а посебно еволуције рудоносних флуида из којих је настала рудна минерализација. Утврђено је да је овај систем настао у периоду пре 86,78 - 85,19 Ma из магматског интрузива који је био богат водом и имао висок оксидативни потенцијал. Током хлађења, из овог магматског интрузива су издвојени веома врели флуиди, који су имали температуре изнад 600°С и висок салинитет. У ...
    Борска металогенетска зона, Тимочки магматски комплекс, порфирска лежишта, високосулфидациона лежишта, флуидне инклузије, рудне парагенезе, геохронологија, хидротермалне алтерације, LA-ICP-MS
    ... different veins by LA-ICP-MS in Chukaru Peki high sulfidation deposit, Serbia. 1 st International Student Conference on Geochemistry and Mineral Deposits, Prague. ГЕНЕЗА ХИДРОТЕРМАЛНОГ Cu-Au СИСТЕМА ЧУКАРУ ПЕКИ (ИСТОЧНА СРБИЈА) 106 139. Velojić, M., Jelenkovic, R., & Cvetkovic ...
    ... magmatic evolution and related Cu–Au mineralization in Bulgaria and Serbia. In Ninth Biennial Meeting of the Society for Geology Applied to Mineral Deposits SGA, Dublin. Dublin: Irish Association for Economic Geology, 861-864. 143. von Quadt, A., Erni, M., Martinek, K., Moll, M., Peytcheva, I. ...
    ... Немачкој.  У јануару 2016. године похађао је десетодневни курс „Resource Economics and Mineral Exploration“ на ETH Универзитету у Цириху, Швајцарска.  У јануару 2017. године похађао курс „Porphyry Copper Deposits: from bottoms to tops“ на Универзитету у Женеви, Швајцарска.  Крајем јануара и почетком ...

  • Pleistocene rhinoceros from Bogovina Cave: the first report of Stephanorhinus hundsheimensis Toula, 1902 (Mammalia, Rhinocerotidae) from Serbia

    Predrag Radović, Miloš Radonjić, Emmanuel Billia (2020)
    Finds of Pleistocene rhinoceros are rare in Serbia, and only one species (the woolly rhinoceros Coelodonta antiquitatis Blumenbach, 1799) has been reported so far. The current paper presents the dental material of an extinct so-called Hundsheim rhinoceros, Stephanorhinus hundsheimensis Toula, 1902 from Bogovina Cave (East ern Serbia). Both the morphological and metric characteristics of the teeth are consis tent with the attribution to S. hundsheimensis. Unfortunately, the rhinoceros material originated from an uncertain geological context, so there is no ...
    rhinoceros, Stephanorhinus hundsheimensis, Serbia
    ... on the western rim of the Bogovina Basin, a tectonic depression filled with up to 380 m thick Upper Oligocene to Upper Miocene sediments with coal deposits (Cvetičanin and Novković, 1975; Petrović, 1977). With 6 km of explored channels, Bogovina Cave is one of the largest in Serbia (Milanović, 2015) ...
    ... Sedimentologija, Paleontologija), 1:328-336. (In Serbian with English translation) Dimitrijević, V.M. 1996. Upper Pleistocene mammals from cave deposits in Serbia. Acta Zoologica Cracoviensia, 39(1):117-120. Dokmanovic, P., Jemcov, I., Milanovic, S., and Hajdin, B. 2003. Hydrogeological risk factors ...
    ... in Belgrade A, 47-50:217-237. Marra, F., Pandolfi, L., Petronio, C., Di Stefano, G., Gaeta, M., and Salari, L. 2014. Reassessing the sedimentary deposits and vertebrate assemblages from Ponte Galeria area (Rome, central Italy): an archive for the Middle Pleistocene faunas of Europe. Earth-Science ...

  • Comprehensive Profiling of Microbiologically Induced CaCO3 Precipitation by Ureolytic Bacillus Isolates from Alkaline Soils

    Olja Šovljanski, Lato Pezo, Jovana Stanojev, Branimir Bajac, Sabina Kovač, Elvira Tóth, Ivan Ristić, Ana Tomić, Aleksandra Ranitović, Dragoljub Cvetković, Siniša Markov (2021)
    MICP process, kinetic study, calcite, vaterite, MALDI-TOF identification, Bacillus licheniformis, Sporosarcina pasteurii
    ... At each sample time, the pH values were measured, and the total volume of inoculated broth (100 mL) was centrifuged (10,000 rpm, 15 min). Any mineral deposits adhered to the bottle walls were removed by scraping with a sterile inoculated needle. The pellets were centrifuged to remove biomass and extra ...
    ... precipitation) were observed in the Urea base broth. The precipitation of inorganic deposits was observed in Urea-CaCl2 and YE-CaCl2 broth. A total volume of inoculated media was centrifuged (10,000 rpm, 15 min) and the deposits were washed out three times by sterile distilled water, dried to constant mass ...
    ... negatively charged bacterial walls [9]. Furthermore, the whole process is reflected in a change of pH value and concentration of dissolved inorganic deposits in a matrix, which is especially expressed during ureolytic activity [2]. Therefore, kinetic pathways of ureolytic activity have been used to better ...

  • Balance between tectonics and sedimentation during geodynamic evolution of the Adria-Europe convergence zone in central Serbia

    Uroš Stojadinović, Nemanja Krstekanić, Bojan Kostić, Tamara Bogdanović (2021)
    ... Lower Cretaceous–Cenomanian depositionwas associated with regional contraction and characterized by the clastic-carbonatic cyclic shelfand slope deposits (i.e., the “para-flysch”). The European fore-arc “para-flysch” sequences,deposited during Berriasian–Aptian times, presently outcrop in the Gledićke ...

  • A contribution to the understanding of hydrochemical properties of thermomineral water on the L’dži locality (eastern part of North Macedonia)

    Hristina Petrova, Katarzyna Wątor, Piotr Rusiniak, Boris Vakanjac, Vesna Ristić Vakanjac, Ewa Kmiecik (2023)
    Regarding the aspect of mineral, thermo-mineral, and thermal waters, on the territory of the Republic of North Macedonia, there are 65 registered locations, of which 8 are categorized as spas. This includes the Kežovica spa, also known as the Štipska spa. In the vicinity of Kežovica Spa is the thermo-mineral L’Dži spring with mineralization around 1.3 g/L and the water temperature at the time of sampling was 50.1 °C. Spring L’Dži is generated by a fault structure and is ...
    thermo-mineral water, water chemistry, hydrochemical properties, L’dži locality, North Macedonia.

  • Towards Sustainable Management of Transboundary Hungarian-Serbian Aquifer

    Zoran Stevanović, Peter Kozák, Milojko Lazić, Janos Szanyi, Dušan Polomčić, Balazs Kovács, Jozsef Török, Saša Milanović, Bojan Hajdin, Petar Papić (2011)
    ... would be assumed to be promising for such inter-ventions. In line with last two proposals the alternative water sources are also analysed. A1luvial deposits along the Danube have the largest potential for water supply of the population and industry but Tisa alluvium should not be neglected. The Danube ...
    ... the most promising sources for the regional water supply of nodhern Serbia. In the vicinity of Apatin, 40-50m thick and very permeable allr.rvial deposits, gravel and sands (average transmissivity T:2 x 10 z *"-t) enable the tapping of some 0.25-0.3m3s-t per 1km distance along the riverbank [10]. ...

  • Минерагенија зеолитских туфова Србије

    Vladan Kašić (2018-02-05)
    Лежишта наших зеолитских туфова (Златокоп, Игрош, Јабланица 1, Беочин, Топоница и Сланци) која су овде била предмет детаљних истраживања, просторно и генетски везана су за вулканске и вулканокластичне стене маринских средина сенонске и неогенске старости и језерске седименте неогене старости и настала су као продукт девитрификације вулканског стакла.Током лабораторијских испитивања при изради ове докторске дисертације, примењене су следеће аналитичке методе: оптичка испитивања петрографских препарата; рендгенска дифракција праха (XRD); скенирајућа електронска микроскопија (СЕМ метода); хемијска карактеризација зеолитских туфова у оквиру ...
    минерагенија, зеолитски туф, Србија, клиноптилолит, хојландит
    ... лит; према IZA – Catalog of deposits) Земља/минерал CEC (meq/100g) Јерменија/Cli 136 Аустралија/Cli 120 Иран/Cli 150-200 Н. Зеланд/Cli 102-122 Словачка/Cli 120-150 Из приложеног се види да вредности коефицијента катјонске измене зеолитских минерала наших лежишта зеолитских туфова ...
    ... природних зеолитских туфова из различитих светских лежишта (Cli – клиноптилолит; Мо – Mordenit, према IZA – Catalog of deposits и Inglezakis and Loizidou, 2002) Земља/минерал Оксидне компоненте, (%) SiO2 Al2O3 Fe2O3 Na2O K2O CaO MgO TiO2 MnO G.Ž. Јерменија/Cli 69,40 13,10 - 0,85 1,80 2,05 - 0 ...
    ... Србије, 225 стр. Mumpton F. A., (1960): Clinoptilolite redefined, The American Mineralogist, vol. 45, March-April,Am. Mineral. 45, 351-369. Mumpton, A. F., (1973): Worldwide deposits and utilisation of natural zeolites. Ind. Minerals, No.73., 30-45. Mumpton F. A. (1988): Occurrence, Properties and ...

  • Geoloski profil planine Avale (severna Šumadija) - uvid u litostratigrafiju i tektonske strukture

    Marinko Toljić, Bojan Glavaš-Trbić, Maja Maleš, Nikola Ranđelović (2022)
    Mezozojske formacije Šumadije dele tektonsko-stratigrafsku evoluciju južnijih delova suture jedinica Adrijskog i Evropskog afiniteta, uključujući gornjojursku obdukciju, krednu subdukciju i paleogenu kontinentalnu koliziju. Finalni rezultat dugovremene evolucije u geodinamički složenom ambijentu su komplikovani tektonski i litostratigrafski odnosi različitih mezozojskih formacija suture. Geološki profil kroz planinu Avalu omogućava uvid u skoro potpunu sukcesiju mezozojskih formacija i prostorne pozicije i kinematiku značajnih tektonskih struktura najsevernijih segmenata suture u Šumadiji. U tektonskom kontekstu, mezozojske formacije okoline Beograda najčešće su interpretirane kao deo Istočne ...
    sutura, parafliš, bazalna navlaka, transkurentni rased

  • The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)

    Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov (2019)
    Geography, Planning and Development,Aquatic Science,Biochemistry,Water Science and Technology
    ... Jurassic and Cretaceous ages. The Triassic deposits are represented by limestones, dolomites, conglomerates and sandstones, whilst the Jurassic deposits are represented by sandstones, clays, conglomerates and marble limestones. The most frequent deposits of the Cretaceous age are limestones, marls and ...
    ... solids—TDS) groundwater (detected at sampling point 4 + 230 m in the tunnel, EC: 5000–10,200 µS/cm) and the water transported by the tunnel, whose mineral content was much lower (Table 3). When the tunnel was in full operating mode and the pressure of the transported water seeping into the hydrogeologic ...

  • Mine surveying works for the purpose of excavating the remaining reserves of bauxite in the deposit of “Podbracan”

    Aleksandar Milutinović, Aleksandar Ganić, Thamer Rayes Diyab, Rade Tokalić, Meri Ganić (2015)
    ... "podbracan" bauxite deposit Bauxite deposit "Podbracan" has a surface of approximately 523,000m2 and is classi�ed as the �rst group of red bauxite deposits by its structure- morphological type and economic importance. The ore body was created during the continental phase of devel- opment between the ...
    ... blind valleys). These limestones are occurring along the rim of the deposit. The overlying beds are made of the upper Cretaceous and Neogene deposits. The upper Cretaceous sedi- ments were discovered furthest to the southeast of the deposit, spreading to the east outside of the deposit. They are ...
    ... are represented by marlstones, marly lime- stones and sandstones with thickness up to 70m. These sediments are moved over the Neogene deposits along the low-angle reverse fault. The longevity of the movement and the dip angle of the reverse faults are not determined, since it is predominantly ...

  • INVENTS: A Hybrid Mine Ventilation Planning and Design System

    Lilić Nikola, Stanković Ranka, Obradović Ivan (2013)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper we ...
    hybrid systems, mine ventilation, expert systems
    ... The first phase of the outlined methodology is data acquisition. In contemporary mining practice extensive and exhaustive investigations of ore deposits are undertaken in order to collect as much information as possible for the planing and design of technological systems for deposit exploitation ...
    ... software package is shown on figure 4. SimVent is a software package that enables mine ventilation simulation in underground exploitation of ore deposits. The global structure of the mathematical model for ventilation simulation in mine ventilation networks, transformed into the SimVent software package ...

  • INVENTS: a hybrid system for subsurface ventilation analysis

    Nikola Lilić, Ranka Stanković, Ivan Obradović (2000)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper we ...
    ... The first phase of the outlined methodology is data acquisition. In contemporary mining practice extensive and exhaustive investigations of ore deposits are undertaken in order to collect as much information as possible for the planing and design of technological systems for deposit exploitation ...
    ... software package is shown on figure 4. SimVent is a software package that enables mine ventilation simulation in underground exploitation of ore deposits. The global structure of the mathematical model for ventilation simulation in mine ventilation networks, transformed into the SimVent software package ...

  • Geotechnical Conditions for Construction of Savski Trg Metro Station as a Part of the Belgrade Metro Line One

    Nemanja Stanic, Dragoslav Rakic, Josip Isek, Slavoljub Simic (2024)
    In order to solve serious traffic congestion in Belgrade, a number of studies regarding the Belgrade Metro construction have been carried out since 1973. However, only in 2019, the routes of the future metro lines 1 and 2 were de-fined as a part of the General Metro Construction Project. The lines are de-signed to intersect at the location of Sava Square, where an interchange met-ro station will be built. It represents a complex geotechnical structure consist-ing of three different ...
    metro station, geotechnical modelling, displacements

  • Mineralni i hemijski sastav čestica u atmosferi zone Kolubarskog basena i uticaj na životnu sredinu

    Željko R. Cvetković (2013-11-18)
    Čestice iz vazduha su prikupljane u blizini termoelektrane i površinskih kopovarudnika uglja u Kolubarskom basenu. Izmereni srednji sadržaji koncentracija rastvornih,nerastvornih i ukupnih taložnih materija na godišnjem nivou prelaze 200 mg/m2dan (K-1, K-3, K-4, K-5). Distribucija čestica na svim lokacijama klasifikovana je na česticeveličine veće od 10 μm, zatim na čestice veličine od 10 μm do 2,5 μm i klase česticaveličine ispod 2,5 μm. Ovakva podela je dala odnos koncentracija inhalatornih irespiratornih čestica po mernim mestima. Skenirajuća elektronska mikroskopija jepokazala ...
    mineral, četica, prašina, leteći pepeo, aerosediment, PM10, teški metali,koncentracija, veličina čestice, Kolubara
    ... D-dolomit, Gl-minerali gline, A-anhidrit. Za aerosedimentane lokaliteta K-4 dobijen je sledeći mineralni sastav. Kvarc je dominantan mineral u oba ispitivana perioda. Sledeći mineral po zastupljenosti je feldspat koji je više prisutan od ostalih minerala dok su ostali minerali slabo zastupljeni ...
    ... međuatomskim rastojanjima za letnji i zimski period K – 1 K – 3 LETO ZIMA LETO ZIMA Ictg d Ǻ mineral Ictg d Ǻ mineral Ictg d Ǻ mineral Ictg d Ǻ mineral 14 10,09 M 17 14,88 Co 16 10,05 M 14 10,03 M 16 7,64 G 16 10,03 M 19 7,64 G 11 5,30 D 17 7,23 Co 17 7,62 G 23 4,46 M ...
    ... međuatomskim rastojanjima za letnji i zimski period K – 5 K – 7 LETO ZIMA LETO ZIMA Ictg d Ǻ mineral Ictg d Ǻ mineral Ictg d Ǻ mineral Ictg d Ǻ mineral 19 10,03 M 16 9,94 M 22 10,00 M 23 7,64 G 22 7,64 G 14 7,62 G 29 7,58 G 94 4,26 Q,G 18 7,16 M 11 6,37 F 19 6,31 F ...

  • Demise of the Wetterstein Carbonate Platform and onset of the Dachstein Carbonate Platform recorded in deep-water successions of the East Bosnian-Durmitor megaunit (Pliješevina, northern Montenegro, Dinarides)

    Milica Mrdak, Eva Wagerer, Milan Sudar, Nevenka Djerić, Martin Đaković, Hans-Jürgen Gawlick (2024)
    Triassic, Carnica event, clay mineralogy, conodont biostratigraphy, Neo-Tethys

  • Sastav i teksture minerala FeO-Fe2O3-TiO2 sistema u vulkanskim stenama i porfirskim ležištima bakra Borske metalogenetske zone

    Aleksandar Luković (2021)
    Proces obrazovanja minerala iz sistema FeO-Fe2O3-TiO2 u uzorcima vulkanskih stena i porfirskih orudnjenja borske zone prikazan kroz pojavu magnetita/hematita i njihovih alteracija. Minerali ove zone su ispitivani optičkim metodama (odbijena i propuštena svetlost), SEM-EDS/BSD, XRPD, LA-ICP-MS metodama. Rezultati ispitivanja su, pored glavnih Fe – Ti oksida, otkrili prisustvo ferijskog ilmenita u hornblenda andezitima I vulkanske faze kao i magnetita sa većim koncetracija Cr u zoni zlotske magnetne anomalije. Ispitivanje uzoraka iz bušotina porfirskih sistema borske zone otkriva postojanje nekoliko ...
    magnetit, hematit, hemoilmenit, Borska metalogenetska zona, porfirska ležišta
    ... the minerals of FeO-Fe2O3-TiO2 system in volcanic rocks and porphyry copper deposits of the Bor metallogenic zone The process of formation of mineral system FeO-Fe2O3-TiO2 in samples from volcanic rocks and porphyry deposits of Bor zone is explained through occurrences of magnetite/hematite and their ...
    ... Ramboz, C., (2001): Sr and Pb isotope study of Au-Cu epithermal and porphyry-Cu deposits from the southern part of the Panagyurishte 93 district, Sredna Gora zone, Bulgaria. In: Piestrzynski A., (eds). Mineral deposits at the beginning of the 21st century. Balkema, Lisse, 539-542. Krstić, B. ...
    ... product of magnetite in same paragenesis. All types are presented through mineral textures and composition of micro and trace elements. Key words: magnetite, hematite, hemoilmenite, Bor metallogenic zone, porphyry deposits Scientific field: Geosciences Scientific subfield: Fundamental and Applied ...

  • Lower Berriasian ammonites from Dedina (Golubac Mountains, eastern Serbia) and their biostratigraphic implication

    Zdenek Vasícek , Dragoman Rabrenović, Petr Skupien, Barbara Radulović (2023)
    Ammonites, Taxonomy, Lower Berriasian, Getic, Northern Tethys, Serbia
    ... ammonite zonation of the deposits around the J/K boundary in Crimea. The basal Berriasian belongs to the Jacobi Zone, which is subdivided into two subzones: Jacobi and Grandis. Recently, Szives and Fozy (2022) presented an account of the ammonite stratigraphy of deposits around the Jurassic-Cretaceous ...
    ... boundary sections between different regions provides important information for solving this problem. The assumption that there are fossiliferous deposits in the area of the J/K boundary on the Serbian section at the Dedina locality initiated an integrated investigation of this site. Ammonites ...
    ... integrated study on belemnites, brachiopods, bi- valves, microfossils, stable isotopes, and magnetostratigraphy. 2. Geological setting The studied deposits of the Dedina area are within the Getic nappe system framework and have large extents and thicknesses. In that area, the Carpatho-Balkanides form ...

  • Geološko-geofizički model dela Timočkog magmatskog kompleksa

    Snežana M. Ignjatović (2014-06-30)
    Timočki magmatski kompleks (TMK) u geotektonskom smislu pripada KarpatoBalkanidimaistočne Srbije, koji su deo Tekijsko-Dakijske jedinice. TMK je nastaotokom kontinuirane vulkanske aktivnosti, koja je trajala oko deset miliona godina iodvijala se generalno u tri faze (Zimmerman et al., 2008, Kolb et al., 2013, Banješević,2006). Pomeranje vulkanskog fronta je išlo od istoka ka zapadu (von Quadt et al., 2002,2003, 2007). Ovaj kompleks pripada tetijskom evroazijskom metalogenetskom pojasu usvetu poznat po ležištima bakra i zlata (Janković, 1990).U doktorskoj disertaciji su prikazani rezultati ...
    Timočki magmatski kompleks, aeromagnetska istraživanja, gravimetrijskaistraživanja, 2D geološko-geofizički model, Valja Strž, magmatsko telo
    ... of epithermal gold mineralization in the Bor metallogenetic zone, Serbia, Yugoslavia - 6th Biennial SGA Meeting, under the general theme "Mineral Deposits at the Beginning of the 21st Century", Krakow, 535-538. Koţelj, D., 2002. Epitermalna mineralizacija zlata Borske metalogenetske zone. M ...
    ... fakultet, Beograd, st. 189. Monthel, J., Vadala, P., Leistel, J.M., Cottard, F., Ilić, M., Štrumberger, A., Tošović, R., Stepanović, A., 2002. Mineral deposits and mining districts of Serbia. Compilation map and GIS databases. BRGM/RC-51448-FR, pp. 67. Nabigian, M.N., 1972. The analytic signal of ...
    ... ). Geološko-geofizički model dela Timočkog magmatskog kompleksa 137 Nineth Biennial Meeting of the Society for Geology Applied to Mineral Deposits SGA, Dublin. Dublin: Irish Association for Economic Geology, 861-864. Vukašinović, S., 2005. Anomalno magnetsko polje i geološka graĎa republike ...

  • Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery

    Maja Milošević, Biljana Đorđević, Mihovil Logar (2020)
    калцит, сирова глина, традиционална керамика, Злакуса
    ... Mineralogy The mineral phases identified in the CIMx sample are kaolinite/ halloysite, mica/illite, smectite, quartz, paragonite, feldspar, calcite and hematite ( ), in accordance with the mineral phases reported by Milošević et al. ( ). Quartz is the most abundant non-clay mineral, while calcite ...
    ... marl, and limestone Quartz conglomerate, sandstone quartz breccia, and siltstone 'Sandstone, slate, and phyllite Metasandstone Piedmont deposits Alluvium Microfauna Research area Lat: 43.7883000 Lon:19.9884700 Fig. 1. Geographical (left) and geological (right) locations of the investigated ...
    ... Baccour H., Medhioub M., Jamoussi F., Mhiri T. & Daoud A. (2008) Mineralogical evaluation and industrial applications of the Triassic clay deposits, southern Tunisia. Materials Characterization, 59, 1613–1622. Barnes G. (2014) The workability of natural clays and clays in the ceramics industry ...