Samsonite

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Samsonite
Samsonite-656898.jpg
Samsonite crystals on matrix from the Samson pit, St. Andreasberg, Harz, Germany (step size: 26 mm × 16 mm × 20 mm, largest crystal 9 mm)
General and classification
chemical formula
  • Ag 4 MnSb 2 S 6
  • MnAg 4 [SbS 3 ] 2
Mineral class
(and possibly department) 		Sulfides, sulfosalts
System no. to Strunz
and to Dana 		2.GA.15 ( 8th edition : II / D.01b appendix)
04/03/12/01
Similar minerals Miargyrite
Crystallographic Data
Crystal system monoclinic
Crystal class ; symbol monoclinic prismatic; 2 / m
Space group P 2 1 / n (No. 14, position 2)Template: room group / 14.2
Lattice parameters a  = 10.3861  Å ; b  = 8.1108 Å; c  = 6.663 Å
β  = 92.639 °
Formula units Z  = 2
Frequent crystal faces {010}, {100}, {110}, {210}, {103}, {101}, { 1 01}, { 3 01}, {111}, { 1 11}
Physical Properties
Mohs hardness 2.5, VHN 100 = 187-212 kg / mm²
Density (g / cm 3 ) 5.51 (measured); 5.461 (calculated)
Cleavage no
Break ; Tenacity clamshell; very brittle
colour steel gray to black, deep red to brown in transmitted light
Line color dark red with an insignificant tinge of brown
transparency opaque, shining through deep red to brown in splinters
shine Metallic luster
Crystal optics
Refractive index n  = extremely high, greater than 3
Pleochroism weak
Other properties
Chemical behavior soluble in a mixture of warm nitric acid and tartaric acid

Samsonite is a very rare mineral from the sulfide class . It crystallizes in the monoclinic crystal system with the chemical formula Ag 4 MnSb 2 S 6 , so it is a silver - manganese - sulfosalt with the basic building block [SbS 3 ] 3− or a neutral silver sulfantimonide in which one atom of silver is replaced by one atom of manganese .

Samsonite develops opaque, prismatic and in the prism zone strongly striped, up to 4 cm large crystals from steel gray to black color. Its type locality is the Samsoner Gang in the Samson mine in Sankt Andreasberg in the Upper Harz , Lower Saxony , Germany .

Etymology and history

View of Sankt Andreasberg with the Samson mine in the middle of the left edge of the picture. The mineral samsonite was named after this pit.

In the summer of 1908, the Royal Mining Inspector Heinrich Werner (* 1872) found an unknown mineral in the "Samson Pit" in Sankt Andreasberg in the Upper Harz Mountains , in the roof of the 29th  section of the Samson corridor, at a depth of approx. 550 m , an unusual formation of the vein was shown. Since the 29th route had already delivered some beautiful fragments of silver ore - including excellent pyrargyrite  - since the 1890s , Werner followed the work in this area very carefully. The ore zone was tectonically thinned 20 to 30 m above the route . As gangue were quartz , calcite , anhydrite and gypsum on, interspersed with galena honeymoon. Two meters above plaster a ausgelängte found himself stibnite - lens in a moderate calcite and a few meters east of it, a Druse , steel-gray in around 60 until 4 cm long crystals "chopped" on quartz had grown up. Some of the prisms were arranged radially in small groups. The largest known samsonite crystal comes from this druse - 4 cm long, 4 mm thick and sitting on calcite and quartz. A second, smaller gland was found five meters above it, from which another 20 bits were recovered.

Werner initially thought the material was miargyrite . Professors Alfred Bergeat and Friedrich Kolbeck , who taught at the Bergakademie Clausthal and Bergakademie Freiberg , respectively , drew Werner's attention to the fact that his discovery could be a previously unknown mineral. Werner then gave the analyst Fraatz in Clausthal 0.5 g of a sample. In addition to silver, antimony and sulfur, the chemical investigation also found 5.86% by weight of manganese, which made it clear that it was actually a new mineral .

The first description of samsonite was made in 1910 by Heinrich Werner and the chemist Fraatz in the journal for crystallography and mineralogy . The authors named the mineral "samsonite" after its type locality .

Type material for the mineral is not defined. Due to the discovery and first description before 1959, samsonite is one of the minerals that are designated as grandfathered by the International Mineralogical Association (IMA) .

In 1954, the then Office for Soil Research in Hanover, together with the Mineralogical Institutes of the Westphalian Wilhelms University in Münster and the Johann Wolfgang Goethe University in Frankfurt am Main, acquired the Werner collection from his heirs, after Werner had decreed that his collection should be accessible to the public must be. Today's Federal Institute for Geosciences and Raw Materials as well as the University of Münster have several specimens and crystals from the original find of this mineral. In March 2006, during the opening hours of the Mineralogical Museum in Münster, some of the samsonite specimens on display from the Heinrich Werner collection, which were among the world's best pieces of the mineral, were stolen.

classification

Already in the now outdated, but still in use 8th edition of the mineral systematics according to Strunz , the samsonite belonged to the mineral class of "sulfides and sulfosalts" and there to the general department of "sulfosalts", where it was appended to the "xanthocone series" with the system -No. II / D.01b and the members Pyrostilpnit and Xanthokon could be found.

The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), also assigns samsonite to the class of "sulfides and sulfosalts", but in the newly defined section of "sulfarsenides, sulfantimonides," Sulfbismutide ". This is further subdivided according to the crystal structure and the possible presence of further sulfur, so that the mineral can be found according to its structure and composition in the subdivision of "Island sulfarsenides (Neso sulfarsenides) etc., without additional sulfur (S)", where it forms the unnamed group 2.GA.15 as the sole representative .

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns samsonite to the class of "sulfides and sulfosalts" and there in the department of "sulfosalts". Here he is the sole representative within the subsection “Sulphosalts with the ratio 3> z / y and the general composition (A + ) i (A 2+ ) j [ByCz], A = metals, B = semi-metals, C = non-metals" to be found in the unnamed group 04/03/12 .

Chemism

Ten microprobe analyzes on samsonite resulted in mean values ​​of the most important components (sum 99.62% by weight) of 45.76% silver (Ag); 25.86% antimony (Sb); 22.25% sulfur (S); 5.74% manganese (Mn) and 0.03% iron (Fe). The empirical formula Ag 4.01 Mn 0.99 Sb 2.01 S 6.00 was calculated from this , which was idealized to Ag 4 MnSb 2 S 6 . Samsonite contains traces of iron and copper .

Are chemically similar Menchettiit , AGPB 2.40 Mn 1.60 Sb 3 As 2 S 12 , Oyonit , Ag 3 Mn 2 Pb 4 Sb 7 As 4 S 24 , and Uchucchacuait , AgMnPb 3 Sb 5 S 12 .

Samsonite was the world's first silver-containing sulfide mineral or sulfosalt with a formula-effective manganese content. Today there are six such minerals - besides the ones listed above, these are also agmantinite , Ag 2 MnSnS 4 , and manganoquadratite , AgMnAsS 3 .

Crystal structure

Crystal structure of samsonite as a “ball-and-stick model”
Color table:
__ Ag     __ Mn     __ Sb     __ S

Samsonite crystallizes in the monoclinic crystal system in the space group P 2 1 / n (space group no. 14, position 2) with the lattice parameters a = 10.3861  Å , b = 8.1108 Å, c = 6.663 Å and β = 92.639 ° as well two formula units per unit cell . Template: room group / 14.2

The manganese atoms are six sulfur atoms in the form of a slightly deformed MnS 6 - octahedron surrounded the antimony atoms of three sulfur atoms trigonal pyramidal. The octahedra are isolated, so they have no common faces, edges or corners, and are linked to one another via the Ag and Sb polyhedra . The Sb atoms are trigonally coordinated , the SbS 3 pyramids are separated from each other. Samsonite contains two types of silver atoms. Ag (1) is surrounded by four sulfur atoms in a distorted tetrahedral manner , with the three crystallographically different sulfur atoms forming the base of a deformed trigonal pyramid with Ag (1) at the top. The [Ag (1) -S] distances of the first three S atoms are slightly shorter than the fourth [Ag-S] bond, which completes the configuration to the deformed tetrahedron. Ag (2) is trigonal-planar surrounded by three (2 + 1) sulfur atoms. In the coordination polyhedra around the three S atoms, the S (1) and S (2) atoms are surrounded by Ag (1), Ag (2), Mn and Sb in a deformed tetrahedral manner. S (3) is deformed trigonal-bipyramidal surrounded by five metal atoms. Ag (1), Ag (1 ′) and Sb form the base, while Ag (2) and Mn are at the top. S (3) is slightly shifted from the base towards Mn. The determined crystal structure was essentially confirmed by Luca Bindi and Michael Evain.

properties

morphology

Prismatic samsonite crystal with clear longitudinal stripes (field of view 0.8 mm)

The morphology of the samsonite crystals was intensively investigated shortly after the discovery of the mineral, which resulted in three different papers on this topic in quick succession. Willy Bruhns submitted the first publication as early as 1911, followed by František Slavík in 1911 and Friedrich Kolbeck and Victor Goldschmidt in 1912. Finally, in 1934 Charles Palache gave a crystallographic description of Samsonite . Already Palache noticed that the four publications differ greatly with regard to the costume of the crystals examined, which is astonishing with regard to the origin of only two closely adjacent drusen.

  • Costume and habitus of samsonite crystals (the same colors mean the same surface shapes)

  • 1. Short prismatic after {110}, very rich in shape and area

  • 2. extensive with {103}, {101}, {110}, {120}, {11 1 } and {10 1 }

  • 3. extensive with {103}, {101}, {110}, {11 1 } and {10 1 }

  • 4. Little area with {103}, {101}, {110}, and {10 1 }

  • 5. Little space with {101}, {110} and {10 1 }

  • 6. extremely little area with {101} and {110}

  • Drawing of samsonite real crystals

Samsonite forms crystals up to 4 cm long and 1 cm thick, which are short prismatic according to {110} and show strong striations in the prism zone parallel to the c-axis [001]. They often come together to form radial aggregates . The prism {110} is almost always dominant and determines the costume, almost always the pinacoids {010} and {100} as well as the prisms {110}, {210}, {103}, {101}, { 1 01 }, { 3 01}, {111} and { 1 11} were observed. The prisms {140}, {130}, {012}, { 5 01}, {212}, { 1 21} and { 4 73} are less common . Occasionally, a pseudorhombic habitus can be observed due to the even development of {101} and { 1 01} . Since they grew up with both ends on pieces of quartz, the majority of the crystals from the first, larger, lower druse had no end faces, while the crystals from the second, smaller, upper druse were significantly smaller than those from the first druse, but almost had well-formed end faces throughout.

In the "Silver Miller Mine", Cobalt in Canada , the samsonite was found in granular aggregates, in "Garpenberg Norra" near Garpenberg in Sweden in the form of tiny crystals and in Příbram , Czech Republic , in pseudorhombic aggregates up to 1 cm × 0.6 cm large crystals, which are partially displaced by tetrahedron and galena.

physical and chemical properties

Deep red translucent samsonite microcrystals on quartz from the Samson pit (field of view 1.5 mm)

The crystals of samsonite are steel gray to black, while their line color is always dark red with an insignificant tinge of brown. The surfaces of the otherwise opaque crystals, which only shine through in deep red to brown in thin splinters, have a metallic sheen , which agrees well with the values ​​for light refraction . Extremely high values ​​for light refraction (n> 3) were identified on the crystals of samsonite .

Under the microscope , the mineral is deep red to brown in transmitted light, and bluish-white to bluish-gray in incident (reflected) light. Numerous deep red internal reflections are characteristic when viewed in immersion oil . Samsonite has no bireflectance, but a clear pleochroism from light olive green to blue-gray. In the case of crossed polars , the mineral shows only weak anisotropy effects , which are only clearly recognizable at the grain boundaries, with moderate rotational colors in shades from dark greenish to bluish to brownish.

Samsonite has no cleavage . Due to its strong brittleness , however , it breaks like quartz , with the fracture surfaces being shell-shaped. With a Mohs hardness of 2.5, the mineral is one of the soft to medium-hard minerals, so it stands between the reference minerals gypsum (hardness 2) and calcite (hardness 3) and, like these, can be more or less well with the fingernail (plaster of paris) or a Score a copper coin (calcite). The Vickers hardness VHN 100 was determined to be 187–212 kg / mm 2 . The measured density for samsonite is 5.51 g / cm³, the calculated density is 5.461 g / cm³.

Samsonite melts easily in the closed tube with the release of Sb vapor, in the open flask with the formation of SO 2 , Sb 2 O 5 and a little Sb 2 O 3 . On the carbon in front of the soldering tube , it first melts slightly and sprayed on, with the subsequent formation of an Sb deposit and an infusible mass, from which a metal grain consisting of Ag and a little Sb emerges when the blowing is interrupted. The remainder gives a manganese reaction after roasting in borax and phosphorus salt.

Samsonite is soluble in a mixture of warm nitric acid (HNO 3 ) and tartaric acid (C 4 H 6 O 6 ), very unstable to pure nitric acid and aqua regia .

Education and Locations

Samsonite is formed by the action of ascending (ascending) hydrothermal solutions that circulate on fissures in the adjacent rock and that contain hydrogen sulfide on the primary minerals. These included the silver mineral dyscrasite , galena , a pale ore (possibly tetrahedrite ) and chalcopyrite as ore minerals , a manganese oxide ( pyrolusite ) and calcite and quartz as gangue . As a result of the action of the H 2 S on the primary minerals, a species-rich following of secondary minerals emerged, which occur as accompanying minerals of the samsonite. To them the silver pebble count Sternbergit , Pyrargyrite , remnants of Pyrolusits, by the presence of manganese pink colored Apophyllit (more precisely Fluorapophyllit- (K) ), realgar and radicals of the primary minerals (Dyskrasit, galena, tetrahedrite, chalcopyrite, calcite and quartz). Lollingite , native silver and cubanite were later observed. The manganese content in both samsonite and fluorapophyllite (K) comes from the decomposition of gray calcite ("brown spar").

As a very rare mineral formation, samsonite could only be described for six sites so far (status 2018). The first and most important site of discovery is the "Samson Pit" in Sankt Andreasberg / Oberharz in Germany, which was the only site for samsonite in the world for almost half a century. In 1960 at the latest, a second site was added, the “Brady Lake Property” of the “Silver Miller Mine” near Cobalt , Ontario , Canada (identified by Paul Ramdohr). Additional sites have been known since the 1990s. They include the Candelaria district in Mineral Co. , Nevada US state , the "Garpenberg Norra" mine near Garpenberg not far from Hedemora in the Swedish province of Dalarnas län , the "uranium mine No. 19" in Dubenec near Příbram in the Central Bohemian Region , the Ag-Au deposit "Guandi" near the city of the same name in Linxi County , Inner Mongolia , China , as well as allegedly Baia Sprie (Felsőbánya) in Maramureș County , Romania .

use

Because of its extreme rarity, samsonite is only of interest to mineral collectors.

See also

literature

  • S. Werner, Fraatz: Samsonite, a manganese-containing silver mineral from St. Andreasberg in the Harz region . In: Centralblatt für Mineralogie, Geologie und Paläontologie . 1910, p. 331–335 ( rruff.info [PDF; 315 kB ; accessed on July 25, 2018]).
  • Charles Palache , Harry Berman , Clifford Frondel : Samsonite [Ag 4 MnSb 2 S 6 ] . In: The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana. Yale University, 1837-1892 . Elements, sulfides, sulfosalts, oxides. 7th edition. tape I . John Wiley and Sons, New York, London, Sydney 1944, ISBN 0-471-19239-2 , pp. 393-395 (English).
  • Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 473 (first edition: 1891).
  • Hans Jürgen Rösler : Textbook of Mineralogy . 4th revised and expanded edition. German publishing house for basic industry (VEB), Leipzig 1987, ISBN 3-342-00288-3 , p. 344 .
  • Samsonite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 (English, handbookofmineralogy.org [PDF; 65 kB ; accessed on June 22, 2019]).
  • Bärbel Sarbas, Wolfgang Töpper: 3.5.2 Samsonite . In: Reiner Ditz, Wolfgang Töpper (Eds.): Gmelin Handbook of Inorganic and Organometallic Chemistry . Mn Manganese: Natural Occurrence. Minerals (Native metal, solid solution, silicide, and carbide. Sulfides and related compounds. Halides and oxyhalides. Oxides of type MO). 8th edition. Springer, Berlin / Heidelberg 1993, ISBN 978-3-662-08909-5 , pp. 135–137 , doi : 10.1007 / 978-3-662-08907-1 (English, limited preview in Google Book Search).

Web links

Commons : Samsonit  - collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d e f g h i j k S. Werner, Fraatz: Samsonite, a manganese-containing silver mineral from St. Andreasberg in the Harz region . In: Centralblatt für Mineralogie, Geologie und Paläontologie . tape 1910 , 1910, pp. 331–335 ( rruff.info [PDF; 315 kB ; accessed on June 22, 2019]).
  2. ^ Hugo Strunz , Ernest H. Nickel : Strunz Mineralogical Tables. Chemical-structural Mineral Classification System . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p.  119 (English).
  3. ↑ a b c Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp.  473 (first edition: 1891).
  4. ^ A b c Charles Palache : Contributions to crystallography: Claudetite; minasragrite; samsonite; native selenium; indium . In: American Mineralogist . tape  19 , 1934, pp. 194–205 (English, rruff.info [PDF; 599 kB ; accessed on June 22, 2019]).
  5. ↑ a b c d e Luca Bindi, Michael Evain: Gram-Charlier development of the atomic displacement factors into mineral structures: the case of samsonite, Ag 4 MnSb 2 S 6 . In: American Mineralogist . tape 92 , no. 5-6 , 2007, pp. 886–891 , doi : 10.2138 / am.2007.2364 (English, rruff.info [PDF; 375 kB ; accessed on July 25, 2018]).
  6. ↑ a b c d e f g h František Slavík: Morphology of Samsonite . In: Bulletin International de l'Académie de L'Empereur Francois Joseph. Class des sciences mathématiques, naturelles et de la médecine . tape XVI , 1911, p. 57-66 .
  7. ↑ a b Samsonite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 (English, handbookofmineralogy.org [PDF; 65  kB ; accessed on June 22, 2019]).
  8. ↑ a b Clifford Frondel : Unit cell and space group of vrbaite (Tl (As, Sb) 3 S 5 ), seligmannite (CuPbAsS 3 ) and samsonite (Ag 4 MnSb 2 S 6 ) . In: American Mineralogist . tape  26 , no. 1 , 1941, p. 5–28 ( rruff.info [PDF; 266 kB ; accessed on July 25, 2018]).
  9. ↑ a b c d e f Willy Bruhns: Crystal form of the Samsonite of St. Andreasberg . In: Annual report of the Lower Saxony Geological Association . tape 4 , 1911, pp. 103-104 .
  10. ↑ a b c d e Carl Hintze, Gottlob Eduard Linck: Handbuch der Mineralogie . Supplementary volume. New minerals. 1st edition. tape 1 . Walter de Gruyter & Co., Berlin / Leipzig 1938, DNB  366194585 , p. 583-587 .
  11. ^ A b c Charles Palache , Harry Berman , Clifford Frondel : Samsonite [Ag 4 MnSb 2 S 6 ] . In: The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana. Yale University, 1837-1892 . Elements, sulfides, sulfosalts, oxides. 7th edition. tape  I . John Wiley and Sons, New York, London, Sydney 1944, ISBN 0-471-19239-2 , pp. 393-395 (English).
  12. ↑ a b c d e f Paul Ramdohr : The ore minerals and their adhesions . 4th, revised and expanded edition. Akademie-Verlag, Berlin 1975, p.  848 .
  13. ^ A b c d e Friedrich Kolbeck , Victor Goldschmidt: About Samsonit von Andreasberg . In: Journal for Crystallography and Mineralogy . tape  50 , no. 4-5 , 1912, pp. 455-458 , doi : 10.1524 / zkri.1912.50.1.455 .
  14. ↑ The Armin Werner Collection. In: aws.musign.de. Museum Osterode, December 13, 2002, accessed on June 22, 2019 .
  15. ↑ a b Samsonite. In: geomuseum.tu-clausthal.de. GeoMuseum of the TU Clausthal , accessed on June 22, 2019 .
  16. ↑ a b Steffen Jahn: Samsonite - now they are gone! Brash mineral theft in Münster / Westphalia . In: Mineral World . tape 17 , no. 3 , 2006, p. 4–6 ( smmp.net [PDF; 243 kB ; accessed on June 22, 2019]).
  17. ↑ Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: March 2019. (PDF; 1.7 MB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, March 2019, accessed May 20, 2019 .
  18. ↑ Ulrich K. Vetter: Samsonit MnAg 4 [SbS 3 ] 2 - The collection item of the month. In: bgr.bund.de. Federal Institute for Geosciences and Natural Resources (BGR), accessed on June 22, 2019 .
  19. ↑ a b Samsonite search results. In: rruff.info. Database of Raman spectroscopy, X-ray diffraction and chemistry of minerals (RRUFF), accessed on June 22, 2019 .
  20. ↑ a b c Samsonite. In: mindat.org. Hudson Institute of Mineralogy, accessed June 22, 2019 .
  21. ↑ Andreas Edenharter, Werner Nowacki: Refinement of the crystal structure of samsonite, (SbS 3 ) 2 Ag 2 III Ag 2 IV Mn VI . In: Journal of Crystallography . tape 140 , no. 1-2 , 1974, pp. 87-89 , doi : 10.1524 / zkri-1974-1-207 ( rruff.info [PDF; 592 kB ; accessed on June 22, 2019]).
  22. ^ Stefan Weiß, Rupert Hochleitner: Silver from A to Z. Noble variety: Silver-containing minerals ... In: Dignified silver. The ore of the coins, the metal of the jewelry, the element with the luster (= Christian Weise [Hrsg.]: ExtraLapis . Band 8 ). Christian Weise Verlag, 1995, ISBN 3-921656-23-0 , ISSN  0945-8492 , p. 88 .
  23. ↑ Petr Korbel, Milan Novák: Mineral Encyclopedia (=  Dörfler Natur ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 52 .
  24. ^ A b Paul Ramdohr : The ore minerals and their adhesions . 3. Edition. Akademie-Verlag, Berlin 1960, p.  731 .
  25. ↑ a b MP Kalinowski: Rambergite, a new polymorph of MnS with hexagonal structure . In: Geologiska Föreningen i Stockholm Förhandlingar . tape 118 , 1996, pp. A53-A54 , doi : 10.1080 / 11035899609546335 (English).
  26. ↑ a b Jiří Litochleb, Vladimír Šrein, Jiří Sejkora, Martin Šefrna: Samsonit z polymetalických žil příbramského uranového ložiska . In: Bulletin mineralogicko-petrologického oddělení Národního muzea v Praze . No. 4-5 , 1997, pp. 172-176 (Czech).
  27. ^ A b Bernhard Pracejus: The ore minerals under the microscope. An optical guide . 2nd Edition. Elsevier, Amsterdam 2015, ISBN 978-0-444-62725-4 , pp. 570–571 (English, limited preview in Google Book Search).
  28. ^ Stefan Schorn and other authors: Samsonit. In: mineralienatlas.de. Mineral Atlas - Fossil Atlas , accessed June 20, 2019 .
  29. ^ A b Albrecht Wilke: The ore veins of St. Andreasberg in the context of the Central Harz vein area (monographs of the German lead-zinc deposits, vol. 2) . In: Supplements to the Geological Yearbook . tape 7 , 1952, pp. 96 .
  30. ↑ Localities for Samsonite. In: mindat.org. Hudson Institute of Mineralogy, accessed June 22, 2019 .
  31. ↑ a b List of locations for samsonite in the Mineralienatlas and Mindat (accessed on June 22, 2019)
  32. ↑ Stephen B. Castor, Gregory C. Ferdock: Minerals of Nevada (Nevada Bureau of Mines and Geology Special Publication 31) . 1st edition. Nevada Bureau of Mines and Geology and University of Nevada Press, Reno and Las Vegas 2004, ISBN 0-87417-540-2 , pp. 393 .
  33. ↑ Zhang Bai-Sheng: Experimental study on the classification of the oxidation zones in Guandi gold-silver deposit and the application of Mn matter phases in sulfide poor silver deposits . In: Mineral Resources and Geology . tape 12 , no. 5 , 1998, pp. 318–323 (Chinese with English abstract).
  34. ↑ Caius I. Superceanu: Contributiuni la paragenezele scheelitului si wolframitului din zacamîntul de minereuri complexe de la Baia Sprie . In: Revista Minelor . tape VIII , 1957, p. 399-404 (Romanian).
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