Agardite Explained

Agardite-(Y), agardite-(Ce), agardite-(Nd), agardite-(La)
Category:	Arsenate minerals
Formula:	(REE,Ca)Cu6(AsO4)3(OH)6·3H2O
Imasymbol:	Arg-Y, Arg-Ce. Agr-Nd, Arg-La^[1]
Strunz:	8.DL.15
Dana:	(Y): 42.05.01.02 (Ce): 42.05.01.02e (Nd): 42.05.01.02b (La): 42.05.01.02a
System:	Hexagonal
Class:	Dipyramidal (6/m) H–M symbol: (6/m)
Symmetry:	P63/m (agardite-(La): unknown space group)
Unit Cell:	a = 13.59, c = 5.89 [Å], Z = 2
Color:	Yellow green
Habit:	Acicular
Cleavage:	None
Fracture:	Conchoidal
Mohs:	3–4
Luster:	Vitreous
Streak:	Greenish white
Gravity:	3.7 (measured), 3.775 (calculated)
Refractive:	nω = 1.725, nε = 1.81
Birefringence:	0.085
Pleochroism:	Yellowish green
References:	^[2] ^[3]

Agardite is a mineral group consisting of agardite-(Y),^{[4] [5]} agardite-(Ce),^[6] agardite-(Nd),^[7] and agardite-(La).^[8] They comprise a group of minerals that are hydrous hydrated arsenates of rare-earth elements (REE) and copper, with the general chemical formula (REE,Ca)Cu₆(AsO₄)₃(OH)₆·3H₂O. Yttrium, cerium, neodymium, lanthanum, as well as trace to minor amounts of other REEs, are present in their structure. Agardite-(Y) is probably the most often found representative. They form needle-like yellow-green (variably hued) crystals in the hexagonal crystal system. Agardite minerals are a member of the mixite structure group, which has the general chemical formula Cu²⁺₆A(TO₄)₃(OH)₆·3H₂O, where A is a REE, Al, Ca, Pb, or Bi, and T is P or As. In addition to the four agardite minerals, the other members of the mixite mineral group are calciopetersite,^[9] goudeyite,^[10] mixite,^[11] petersite-(Ce),^[12] petersite-(Y),^{[13] [14]} plumboagardite,^[15] and zálesíite.^[16]

Agardite-(Y) from the Bou Skour mine in Djebel Sarhro, Morocco was the first of the agardite-group minerals to be characterized.^[17] It was described by Dietrich in 1969 and was named after Jules Agard, a French geologist at the Bureau de Recherches Géologiques et Minières, Orléans, France.^[18] Agardite-group minerals have subsequently been found in Germany,^[19] Czech Republic,^[20] Greece,^[21] Italy,^[22] Japan,^[23] Namibia,^[24] Poland,^[25] Spain,^[26] Switzerland,^[27] the United Kingdom,^[28] and the United States.^[29]

See also

• List of minerals

Further reading

• Aufschluss 1977(5), 177–183.
• Steen, H. (2005): Ein Neufund von Agardit-(Y) aus Rotenbach im Feldberggebiet (südlicher Schwarzwald). Der Erzgräber 19, 70–72.
• Wittern: "Mineralfundorte in Deutschland", Schweizerbart (Stuttgart), 2001.*Wittern, A. (1995) Mineralien finden im Schwarzwald.
• Lapis 1985(11), 31–32.
• S. Weiss: "Mineralfundstellen, Deutschland West", Weise (Munich), 1990
• Walenta, K. and Theye, T. (2004): Agardit-(Ce) von der Grube Clara im mittleren Schwarzwald. Aufschluss 55, 17–23. [with analysis of Johann material showing Nd > La].
• Emser Hefte 15(3), 2–40 (1994).
• Heckmann, H. & Schertl, H.-P. (1990): Der Niederbergische Erzbergbau und seine Mineralien. Emser Hefte, 11 (2), 2–40.
• Pekov, I. V., Chukanov, N. V., Zadov, A. E., Voudouris, P., Magganas, A. and Katerinopoulos, A. (2010) Agardite-(Nd), IMA 2010–056. CNMNC Newsletter No. 7, February 2010, page 30; Mineralogical Magazine, 75, 27–31.
• Pekov, I. V., Chukanov, N. V., Zadov, A. E., Voudouris, P., Magganas, A., Katerinopoulos, A. (2011): Agardite-(Nd), NdCu₆(AsO₄)₃(OH)₆·3H₂O from the Hilarion Mine, Lavrion, Greece: mineral description and chemical relations with other members of the agardite-zálesíite solid-solution system. Journal of Geosciences, 56, 249–255.
• Ambrino, P., Brizio, P., Ciriotti, M. E., Finello, G., Marello, B. (2009). Minerali della pietra di Luserna. AMI. CD-ROM.
• Piccoli, G. C., Maletto, G., Bosio, P., Lombardo, B. (2007). Minerali del Piemonte e della Valle d'Aosta. Associazione Amici del Museo "F. Eusebio" Alba, Ed., Alba (Cuneo) 607 pp.
• Stara, P., Rizzo, R., Brizzi G., (1993): Sarrabus Miniere e Minerali. Edito a cura dell'EMSA e "varie associazioni mineralogiche", 208 pp.
• Stara, P., Rizzo, R., Tanca, G. A. (1996): Iglesiente e Arburese. Miniere e Minerali. Edito a cura dell'EMSA e "varie associazioni mineralogiche", Volume 2, 192 pp.
• Olmi F., Sabelli C., Santucci, A., Brizzi, G. (1995): I silicati e i vanadati di Ozieri (SS). Rivista Mineralogica Italiana, 2/1995, 145–160.
• Vecchi, F., Rocchetti, I., Gentile, P. (2013): Die Mineralien des Granits von Predazzo, Provinz Trient, Italien. Mineralien-Welt, 24(6), 98–117.
• Ricordo di Cristel Puecher da Roveda; F. Maiello, P. Ferretti; 2009*Rocchetti I., Gentile P. and Ferretti P. (2012): La Miniera di Frattasecca presso Malga Broi (Novaledo, Trentino-Alto Adige). Storia e nuove segnalazioni mineralogiche. Studi Trentini di Scienze Naturali, 92, p. 167–180.
• Bortolozzi G., Blass G., Boscardin M., Rocchetti I. and Ferretti P. (2013): La Miniera di Cinquevalli (Valsugana, Trentino-Alto Adige): aggiornamento sulle specie accertate negli ultimi anni. Studi Trent. Sci. Nat., 93, p. 149–165.
• Paolo Gasparetto, Erica Bittarello, Andrea Canal, Lara Casagrande, Marco E. Ciriotti, Bruno Fassina, Paolo Ferretti, Sergio Pegoraro, Fabio Tosato, Paolo Zammatteo (2014): I lavori minerari del Rio Ricet, Vignola, Falesina, Trento. Micro, 12, 50–123.
• Senesi, F. & Sabelli, C. (1999): Gli arseniati degli antichi scavi di Valle S. Caterina (Campiglia Marittima). Rivista Mineralogica Italiana, 23(1), 51–55.
• The Mineral Species of Japan (5th ed) Matsubara.
• Yamada, S. (2004) Nihonsan-koubutsu Gojuon-hairetsu Sanchi-ichiranhyou (111 pp.).
• Jimenez R., Joda L., Jorda R., Prado P. (2004) - Madrid: la mineria Metallica desde 1417 hasta nuestros dias. Bocamina, n°14, pp: 52–89.
• Tanago, J. G., Lozano, P. L., Larios, A., La Iglesia, A. (2012) Stokesite crystals from La Cabrera, Madrid, Spain. Mineralogical Record 43: 499–508.
• Collection of the Geominero Museum of Madrid; Tanago, J. G., Lozano, P. L., Larios, A., La Iglesia, A. (2012) Stokesite crystals from La Cabrera, Madrid, Spain. Mineralogical Record 43: 499–508.
• Meisser, N. (2012): La minéralogie de l'uranium dans le massif des Aiguilles Rouges. Matér. Géol. Suisse, Sér. géotech. 96, 183 p.
• Embrey & Symes, 1987, 40 – "Minerals of Cornwall and Devon"]; Peter G. Embrey (1978) Fourth Supplementary List of British Minerals. Mineralogical Magazine 42: 169–177.
• Cooper & Stanley, 1990, 76 – "Minerals of the English Lake district".
• Schultenite: Symes, R.F., Wirth, M., Mineral Mag. (1990), 54, p. 659.
• Mineralien Welt 1/93:44.
• Rocks & Minerals 83:1 pp. 65–69.
• NBMG Spec. Pub. 31 Minerals of Nevada; Rocks & Minerals (2010) 85: 512–524.
• Jensen, M. (1993): Update on the mineralogy of the Majuba Hill mine, Pershing County. Mineralogical Record. 24, 171–180.
• Natural History Museum Vienna collection; Jensen, M. (1993): Update on the mineralogy of the Majuba Hill mine, Pershing County. Mineralogical Record. 24, 171–180.
• R&M 77:5 p. 298–305.
• Anthony, Bideaux, Bladh, Nichols: "Handbook of Mineralogy", Vol. 4, 2000.
• Northrop, Minerals of New Mexico, 3rd Rev. Ed., 1996.
• Micro Probe Volume VI Number 8; Rocks and Minerals, 66:6, p. 453.

External links

• RRUFF Project

Notes and References

1. Warr. L.N.. 2021. IMA–CNMNC approved mineral symbols. Mineralogical Magazine. 85. 3. 291–320. 10.1180/mgm.2021.43. 2021MinM...85..291W. 235729616. free.
2. http://www.mindat.org/min-48.html Agardite
3. http://www.webmineral.com/data/Agardite-%28Ce%29.shtml Agardite
4. Dietrich J. E., Orliac M., Permingeat F. (1969) L’agardite, une nouvelle espèce minérale, et le problème du chlorotile, Bulletin de la Société Française de Minéralogie et de Cristallographie 92, 420–434.
5. Nickel E. H., Mandarino J. A. (1987) Procedures involving the IMA Commission on New Minerals and Mineral Names and guidelines on mineral nomenclature, American Mineralogist 72, 1031–1042.
6. Walenta K., Theye T. (2004) Agardite-(Ce) of the Clara mine in the central Black Forest, Aufschluss 55, 17–23.
7. Pekov I. V., Chukanov N. V., Zadov A. E., Voudouris P., Magganas A., Katerinopoulos A. (2011) Agardite-(Nd), NdCu₆(AsO₄)₃(OH)₆·3H₂O, from the Hilarion Mine, Lavrion, Greece: mineral description and chemical relations with other members of the agardite-zálesíite solid-solution system, Journal of Geosciences 57, 249–255.
8. Fehr T., Hochleitner R. (1984) Agardite-La. Ein neues mineral von Lavrion, Griechenland, Lapis 9, 22–37.
9. Sejkora J., Novotný P., Novák M., Šrein V., Berlepsch P. (2005) Calciopetersite from Domašov nad Bystricí, Northern Moravia, Czech Republic, a new mineral species of the mixite group, The Canadian Mineralogist 43, 1393–1400.
10. Wise W. S. (1978) Parnauite and goudeyite, two new copper arsenate minerals from the Majuba Hill Mine, Pershing County, Nevada, American Mineralogist 63, 704–708.
11. Schrauf A. (1880) Ueber Arsenate von Joachimsthal. 1. Mixit, ein neues Kupferwismuthhydroarsenat, Zeitschrift für Krystallographie und Mineralogie (in German) 4, 277–285.
12. Williams P. A., Hatert F., Pasero M., Mills S. J. (2014) IMA Commission on new minerals, nomenclature and classification (CNMNC) Newsletter 20. New minerals and nomenclature modifications approved in 2014. Mineralogical Magazine 78, 549–558.
13. Peacor D. R., Dunn P. J. (1982) Petersite, a REE and phosphate analog of mixite, American Mineralogist 67, 1039–1042.
14. Nickel E. H., Mandarino J. A. (1987) Procedures involving the IMA Commission on New Minerals and Mineral Names and guidelines on mineral nomenclature, American Mineralogist 72, 1031–1042.
15. Walenta K., Theye T. (2005) Plumboagardite, a new mineral of the mixite group from an occurrence in the Southern Black Forest, Neues Jahrbuch für Mineralogie, Abhandlungen 181, 219–224.
16. Sejkora J., Rídkošil T., Šrein V. (1999) Zálesíite, a new mineral of the mixite group, from Zálesí, Rychlebské hory Mts., Czech Republic, Neues Jahrbuch für Mineralogie, Abhandlungen 175, 105–124.
17. Dietrich J. E., Orliac M., Permingeat F. (1969) L’agardite, une nouvelle espèce minérale, et le problème du chlorotile, Bulletin de la Société Française de Minéralogie et de Cristallographie, 92, 420–434.
18. Anthony J. W., Bideaux R. A., Bladh K. W., and Nichols M. C. (1990) Handbook of Mineralogy, Mineral Data Publishing, Tucson Arizona, USA, by permission of the Mineralogical Society of America.
19. K. Walenta: "Die Mineralien des Schwarzwaldes", Weise (Munich), 1992.
20. Sejkora J., Pauliš P., Kopista J.: Agardit-(Y) z ložiska Sn-W Cínovec v Krušných horách (Česká republika). Bulletin mineralogicko-petrografického oddělení Národního muzea v Praze, 2011, 19, 1, 64–68.
21. LAPIS 24 (7/8) 1999; Wendel, W. and Markl, G. (1999) Lavrion: Mineralogische Klassiker und Raritäten für Sammler. LAPIS 24 (7/8): 34–52.
22. Palenzona, A., Armellino, G., Bulgarelli, G. (1994): Le agarditi della Liguria. Rivista Mineralogica Italiana, 4/1994, 354–356.
23. Anthony, Bideaux, Bladh, Nichols: "Handbook of Mineralogy", Vol. 4, 2000.
24. Gebhard, G. (1999): Tsumeb II. A Unique Mineral Locality. GG Publishing, Grossenseifen, Germany.
25. Siuda R., K. Gal-Solymos, Kruszewski L., 2006: Agardite-(La)-duftite and scorodite-köttigite-like mineral paragenesis from supergenic zone of the Miedzianka deposit (Rudawy Janowickie Mts., Poland) – preliminary report. Mineralogia Polonica Special Papers, 29, 192–195.
26. Anthony, Bideaux, Bladh, Nichols: "Handbook of Mineralogy", Vol. 4, 2000.
27. Stalder, H. A., Wagner, A., Graeser, S. and Stuker, P. (1998): "Mineralienlexikon der Schweiz", Verlag Wepf & Co. (Basel), p. 24.
28. Goley, P. and Williams R. (1995) Cornish Mineral Reference Manual. Endsleigh Publications.
29. Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 323.