Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall:
Gespeichert in:
| Beteilige Person: | |
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| Format: | Hochschulschrift/Dissertation Buch |
| Sprache: | Englisch |
| Veröffentlicht: |
Halle an der Saale
Landesamt für Denkmalpflege und Archäologie Sachsen-Anhalt, Landesmuseum für Vorgeschichte
2021
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| Schriftenreihe: | Forschungsberichte des Landesmuseums für Vorgeschichte Halle
Band 20 : Himmelsscheibe von Nebra. "Der Aufbruch zu neuen Horizonten" DFG-Projekt FOR550 |
| Schlagwörter: | |
| Links: | http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=033091833&sequence=000001&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA |
| Beschreibung: | Auf dem Einband: Himmelsscheibe von Nebra. "Der Aufbruch zu neuen Horizonten" DFG-Projekt FOR550 |
| Umfang: | 96 Seiten Illustrationen, Diagramme, Karten |
| ISBN: | 9783948618292 |
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| 245 | 1 | 0 | |a Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall |c Nicolas Meyer ; herausgegeben von Harald Meller |
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Datensatz im Suchindex
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| adam_text | Inhalt Gregor Borg and Harald Meller From the Mountains through the Rivers to the Sky ֊ the Carnon River Mining District in Cornwail as source for the gold of the Sky Disk of Nebra....................................................................................7 Nicolas Meyer Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall Abstract........................................................................................................................................................................... 23 Acknowledgements........................................................................................................................................................24 1 Introduction..................................................................................................................................................................25 ід Regional geology....................................................................................................................................25 1.2 Location and history of the deposits.....................................................................................................27 1.2.1 The Nangiles Mine.........................................................................................................................27 1.2.2 The Poldice Mine...........................................................................................................................29 2 Methodology................................ 30 2.1
Hard rock samples.................................................................................................................................30 2.2 Placer sample locations......................................................................................................................... 30 2.3 Gold Nuggets Extraction............................................................. :....................................................... 31 2.4 Geochemical Analyses..........................................................................................................................31 2.5 Optical Microscopy............................................................................................................................... 31 2.6 Scanning Electron Microscope/EDX-Analysis.....................................................................................31 2.6.1 EDX-based geochemical composition of minerals....................................................................... 31 2.6.2 EDX-based analyses of gold micro-nuggets..................................................................................32 3 Results..........................................................................................................................................................................33 3.1 The Nangiles Mine................................................................................................................................33 3.1.1 Microscopical investigations and mineral chemistry of samples from the Nangiles Mine......35 3.1.1.1 Ore
Minerals.......................................................................................................................... 35 3.1.1.1.1 Sphalerite........................................................................................................................35 3.1.1.1.2 Pyrite.............................................................................................................................. 36 3.1.1.1.3 Chalcopyrite................................................................................................................... 37 3.1.1.1.4 Cassiterite...................................................................................................................... 38 3.1.1.1.3 Arsenopyrite................................................................................................................... 38 3.1.1.1.6 Galena............................................................................................................................ 39 3.1.1.1.У Accessory ore minerals...................................................................................................40 3.1.1.2 Rock-forming minerals......................................................................................................... 40 3.1.1.2.2 Quartz............................................................................................................................41 3.1.1.2.3 Tourmaline.................................................................................................................... 41 3.1.1.2.4 Chlorite-group
minerals................................................................................................ 42 3.1.1.2.5 Accessory gangue minerals........................................................................................... 42 3.1.1.3 Structural fabrics and mineralisation styles....................................................................... 43 3.1.2 Geochemical analysis of hard rock samples................................................................................43 3.1.2.1 Correlations..........................................................................................................................44 3.2 The Poldice Mine..................................................................................................................................46 į I vrtoch fltB «wtortüNI t I j
3-2.1 Microscopical investigations and mineral chemistry of samples from the Poldice Mine.....47 3.2.1.1 Ore Minerals........................................................................................................................48 3.2.1.1.1 Arsenopyrite................................................................................................................. 48 3.2.1.1.2 Chalcopyrite.................................................................................................................49 3.2.1.1.3 Sphalerite..................................................................................................................... 50 3.2.1.1.4 Pyrite/Marcasite...........................................................................................................51 3.2.1.1.5 Cassiterite..................................................................................................................... 52 3.2.1.1.6 Wolframite.................................................................................................................. 53 3.2.1.13 Accessory ore minerals................................................................................................. 54 3.2.1.2 Rock-forming minerals...................................................................................................... 55 3.2.1.2.1 Lithic clasts...................................................................................................................55 3.2.1.2.2
Quartz.......................................................................................................................... 55 3.2.1.2.3 Chlorite-group minerals...............................................................................................55 3.2.1.2.4 Tourmaline...................................................................................................................55 3.2.1.23 Accessory minerals...................................................................................................... 56 3.2.1.3 Structuralfabrics and mineralisation styles.....................................................................56 3.2.2 Geochemical analyses of hard rock samples.............................................................................57 3.2.2.1 Correlation......................................................................................................................... 60 3.3 Results from stream sediment samples............................................................................................. 60 3.3.1 Micro-nuggets............................................................................................................................... 60 3.3.1.1 Micro-nuggets without detectable silver content on surface.............................................. 61 3.3.1.1.1 Micro-nuggets irregular in shape...................................................................................62 3.3.1.1.2 Subangular to subrounded micro-nuggets....................................................................63 3.3.1.1.3 Round to
oval micro-nuggets......................................................................................... 64 3.3.1.2 Micro-nuggets with detectable silver contents on the surface............................................64 3.3.1.2.1 Angular and irregularly shaped micro-nuggets.......................................................... 65 3.3.1.2.2 Subangular to subrounded micro-nuggets....................................................................65 3.3.2 Placer samples.............................................................................................................................. 67 3.3.3 Geochemical composition of stream sediments..........................................................................69 3.3.3.1 Gold and silver concentrations in stream sediments..........................................................69 3.3.3.2 Base metal concentrations in stream sediments................................................................. 69 3.3.3.3 Tin and tungsten concentration in stream sediments........................................................ 70 3.33.4 Arsenic and sulphur concentrations in stream sediments.................................................. 71 4 Discussion................................................................................................................................................................... 72 4.1 Paragenetical evolution of the mineral composition of the Nangiles Mine and the Poldice
Mine................................................................................................................................... 72 4.2 Interpretation of paragenetic evolution and mineral chemistry data................................................74 4.3 Geochemical composition of hard rock samples................................................................................. 78 4.4 Origin and modification of micro-nuggets......................................................................................... 79 4.5 Interpretation of stream sediment samples........................................................................................ 80 5 Conclusions.................................................................................................................................................................82 5.1 Metallogenetic conclusions.................................................................................................................. 82 5.1.1 Hard rock samples.........................................................................................................................82 5.1.2 Stream sediment samples............................................................................................................ 82 5.1.3 Gold micro-nuggets...................................................................................................................... 83 5.2 Geoarchaeological resume................................................................................................................... 83
Bibliography................................................................................................................................................................... 84 Source of figures............................................................................................................................................................ 85 List of abbreviation....................................................................................................................................................... 86 Mineral abbreviation and composition...................................................................................................................... 86 Appendix 87
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| series2 | Forschungsberichte des Landesmuseums für Vorgeschichte Halle Himmelsscheibe von Nebra. "Der Aufbruch zu neuen Horizonten" DFG-Projekt FOR550 |
| spellingShingle | Meyer, Nicolas Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall Forschungsberichte des Landesmuseums für Vorgeschichte Halle Himmelsscheibe von Nebra (DE-588)4801903-3 gnd Metallanalyse (DE-588)4169566-5 gnd Herkunft (DE-588)4120440-2 gnd Gold (DE-588)4157819-3 gnd |
| subject_GND | (DE-588)4801903-3 (DE-588)4169566-5 (DE-588)4120440-2 (DE-588)4157819-3 (DE-588)4010579-9 (DE-588)4113937-9 |
| title | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall |
| title_auth | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall |
| title_exact_search | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall |
| title_full | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall Nicolas Meyer ; herausgegeben von Harald Meller |
| title_fullStr | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall Nicolas Meyer ; herausgegeben von Harald Meller |
| title_full_unstemmed | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall Nicolas Meyer ; herausgegeben von Harald Meller |
| title_short | Petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the Carnon River Mining District, Cornwall |
| title_sort | petrological investigations of polymetallic vein deposits and auriferous tin placer deposits of the carnon river mining district cornwall |
| topic | Himmelsscheibe von Nebra (DE-588)4801903-3 gnd Metallanalyse (DE-588)4169566-5 gnd Herkunft (DE-588)4120440-2 gnd Gold (DE-588)4157819-3 gnd |
| topic_facet | Himmelsscheibe von Nebra Metallanalyse Herkunft Gold Cornwall Hochschulschrift |
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