Lithiophilite

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Lithiophilite
Lithiophilite-mu01a.jpg
Dark brown, intergrown lithiophilite crystals from the Emmons Quarry , Uncle Tom Mountain , Oxford County (Maine)
Size: 8.8 cm × 8.1 cm × 3.2 cm
General and classification
other names

Lithiophylite

chemical formula
  • LiMn 2+ [PO 4 ]
  • Li (Mn 2+ , Fe 2+ ) [PO 4 ]
Mineral class
(and possibly department) 		Phosphates, arsenates and vanadates
System no. to Strunz
and to Dana 		8.AB.10 ( 8th edition : VII / A.02)
01/38/08/02
Crystallographic Data
Crystal system orthorhombic
Crystal class ; symbol orthorhombic-dipyramidal; 2 / m  2 / m  2 / m
Space group Pbnm (No. 62, position 3)Template: room group / 62.3
Lattice parameters a  = 4.75  Å ; b  = 10.45 Å; c  = 6.11 Å
Formula units Z  = 4
Frequent crystal faces {010}, {011}, {021}, {111}, {100}, {110}, {130}, {140}
Twinning rarely contact twins after {130}
Physical Properties
Mohs hardness 4 to 5
Density (g / cm 3 ) measured: 3.445 to 3.50; calculated: 3.433
Cleavage perfect after {100}, good after {010}
Break ; Tenacity uneven to slightly scalloped
colour reddish brown, yellowish brown to honey yellow, salmon pink, blue gray to gray; colorless to light yellow or pink in transmitted light
Line color gray-white
transparency transparent to translucent
shine Resin gloss to glass gloss
Crystal optics
Refractive indices n α  = 1.663 to 1.685
n β  = 1.663 to 1.685
n γ  = 1.673 to 1.691
Birefringence δ = 0.010
Optical character biaxial positive
Axis angle 2V = 30 ° to 70 ° (measured); 68 ° (calculated)
Pleochroism weak:
X = deep pink
Y = light greenish yellow
Z = light pink
Other properties
Chemical behavior Easily soluble in hydrochloric acid

Lithiophilite is a rather seldom occurring mineral from the mineral class of "phosphates, arsenates and vanadates" with the chemical composition LiMn [PO 4 ] and therefore, chemically speaking, a lithium - manganese - phosphate .

However, lithiophilite forms a gapless series of mixed crystals with triphyline (LiFePO 4 ), which is why a small proportion of manganese is usually replaced ( substituted ) by iron when it occurs in association with it . The mixed formula is given in various sources as Li (Mn 2+ , Fe 2+ ) [PO 4 ].

Lithiophilite crystallizes in the orthorhombic crystal system and occasionally develops sharp-edged, short to long prismatic and flat crystals . Most of the time, however, it is found in coarsely crystalline or granular to coarse mineral aggregates and fissures.

In its pure form, lithiophilite is colorless and transparent, in the transmitted light microscope it is also light yellow or pink. However, due to multiple refraction due to lattice construction defects or polycrystalline formation, it can also be translucent white and, due to foreign admixtures, take on a reddish-brown, yellowish-brown to honey-yellow or salmon-pink, blue-gray to gray color.

Etymology and history

Lithiophilit was first discovered in the lithium-rich granite - pegmatites in the quarry Branchville (also Fillow ) near the same location in Fairfield County of the US state of Connecticut. It was first described in 1878 by George Jarvis Brush and Edward Salisbury Dana , who used the mineral based on its lithium content and based on the ancient Greek word φιλία philía for friendship (from φίλος philos , German for 'friend' ), which means "friend of lithium", named.

The type material of the mineral is in the Mineralogical Collection of Yale University in New Haven (Connecticut) , USA under the catalog no. 3.5641 and 3.5645 as well as in the Muséum national d'histoire naturelle under the number 78.32 .

classification

Already in the outdated 8th edition of the mineral classification according to Strunz , the lithiophilite belonged to the mineral class of "phosphates, arsenates and vanadates" and there to the division of "anhydrous phosphates, arsenates and vanadates without foreign anions " (medium-sized cations and others), where it belongs together with ferrisicklerite , heterosite , natrophilite , purpurite , sicklerite and triphyline, the "triphyline series" with the system no. VII / A.02 formed.

In the last revised and updated Lapis mineral directory by Stefan Weiß in 2018 , which, out of consideration for private collectors and institutional collections, is still based on this classic system of Karl Hugo Strunz , the mineral was given the system and mineral number. VII / A.02-20 . In the "Lapis system" this also corresponds to the section "Anhydrous phosphates [PO 4 ] 3- , without foreign anions" (medium-sized cations: Fe-Mn predominantly), where lithiophilite together with ferrisicklerite, heterosite, Karenwebberit , Maricit , Natrophilit , Purpurite, sicklerite, simferite and triphyline form an independent but unnamed group.

The 9th edition of Strunz's mineral systematics , which has been valid since 2001 and updated by the International Mineralogical Association (IMA) until 2009, also classifies the lithiophilite in the category of “phosphates etc., without further anions , without H 2 O”. However, this is further subdivided according to the relative size of the cations involved , so that the mineral can be found according to its composition in the sub-section “With medium-sized cations”, where it can be found together with ferrisicklerite, heterosite, natrophilite, purpurite, sicklerite, simferite and triphylenet "Triphyline group" with the system no. 8.AB.10 forms.

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the lithiophilite to the class of "phosphates, arsenates and vanadates" and there in the department of "anhydrous phosphates etc.". Here it is together with triphylene and natrophilite in the " triphylene group " with the system no. 38.01.01 can be found in the subsection “Anhydrous phosphates etc. A + B 2+ XO 4 ”.

Chemism

The idealized, theoretical composition of lithiophilite (LiMn [PO 4 ]) consists of 4.43% lithium (Li), 35.03% manganese (Mn), 19.75% phosphorus (P) and 40.80% oxygen (O ). The samples from the type locality of the mineral analyzed by Horace L. Wells also contained small amounts of iron and traces of sodium, silicon and water. In other samples from Buckfield (Maine) traces of calcium and from the Foote Mine near Kings Mountain (North Carolina) small amounts of aluminum could be detected.

Crystal structure

Lithiophilite crystallizes isotypically with olivine in orthorhombic symmetry in the space group Pbnm (space group no. 62, position 3) with the lattice parameters a  = 4.75  Å ; b  = 10.45 Å and c  = 6.11 Å and 4 formula units per unit cell . Template: room group / 62.3

Education and Locations

Macro photograph of pale honey yellow prismatic lithiophilite crystals from the Foote Lithium Co. Mine, Kings Mountain (North Carolina) , USA
Field of view: 3.0 mm

Lithiophilit formed primarily in granite - Pegmatiten and is generally provided with secondary caused by weathering minerals associated as inter alia Dickinsonit , Eosphorit , Fairfieldit , heterosite, Hureaulith , Purpurit, Reddingit , Sicklerit and Triploidit . Often these also form pseudomorphs around a still unweathered core of lithiophilite. Other possible parageneses are albite , amblygonite , beryl , fillowite , graftonite and rhodochrosite .

As a rather seldom occurring mineral formation, lithiophilite can sometimes be abundant at various sites, but overall it is not very common. So far, around 160 sites for lithiophilite have been documented (as of 2019). In addition to its type locality , the Branchville quarry , the mineral occurred in the US state of Connecticut in mineral samples that were produced during the construction of US Route 7 near Brookfield in Fairfield County and in mineral samples from the Schoonmaker pit (also known as the Cramer pit ) and the Strickland quarry (also Eureka ) at Collins Hill in Middlesex County . Other well-known locations in the USA are in the states of Arizona, California, Colorado, Idaho, Maine, New Mexico, North Carolina, South Dakota and Wisconsin.

Worth mentioning due to the extraordinary lithiophilite finds are, among others, Karibib in Namibia and Kitumbe in Rwanda , where extensive masses of up to one meter in size have been found. The findings in the Foote Lithium Co. mine near Kings Mountain (North Carolina) in the USA, where the crystals measure only a few millimeters, are almost perfectly developed, are also outstanding .

In Germany, lithiophilite has so far only been discovered in Saxony in the Sauberg mine near Ehrenfriedersdorf in the Erzgebirge district and in a pegmatite tunnel near Wolkenburg / Mulde in the Zwickau district.

In Austria they found the mineral so far only in a spodumene trial mining on fire back (see also mining in Carinthia ), on Windeck mountain in Mieslingtal ( municipality Spitz ) in Lower Austria and in the quarry Gupper in Germany Berger Gemeindeteil Hinterleiten in Styria.

Lithiophilite is still known worldwide from Argentina, Ethiopia, Australia, Brazil, China, Finland, France, Ireland, Italy, Canada, Madagascar, Mozambique, Namibia, Norway, Poland, Portugal, Romania, Russia, Rwanda, Sweden, Zimbabwe and South Africa.

use

As an ore, lithiophilite is of no economic importance.

See also

literature

  • GJ Brush, ES Dana: On a new and remarkable mineral locality in Fairfield County, Connecticut; with a description of several new species occurring there. First paper . In: American Journal of Science and Arts . tape 116 , 1878, pp. 33-46; 114–123 (English, rruff.info [PDF; 1.3 MB ; accessed on June 7, 2019] Lithiophilite from Se. 115 (PDF p. 20)).
  • Sigmund Geller, Jorge L. Durand: Refinement of the structure of LiMnPO 4 . In: Acta Crystallographica . tape 13 , no. 4 , 1960, p. 325–331 , doi : 10.1107 / S0365110X60002521 (English).
  • Arthur Losey, John Rakovan, John M. Hughes, Carl A. Francis, M. Darby Dyar: Structural variation in the lithiophilite-triphylite series and other olivine-group structures . In: The Canadian Mineralogist . tape 42 , 2004, p. 1105–1115 (English, rruff.info [PDF; 1,2 MB ; accessed on June 7, 2019]).
  • Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason , Abraham Rosenzweig: Dana's New Mineralogy . 8th edition. John Wiley & Sons, New York et al. 1997, ISBN 0-471-19310-0 , pp. 701 .

Web links

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

Individual evidence

  1. ^ Helmut Schrätze , Karl-Ludwig Weiner : Mineralogie. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp.  612, 929 .
  2. ↑ a b c d 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.  426 (English).
  3. ↑ Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: March 2019. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, March 2019, accessed June 9, 2019 .
  4. ↑ a b c 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.  630 .
  5. ↑ a b David Barthelmy: Lithiophilite Mineral Data. In: webmineral.com. Retrieved June 9, 2019 .
  6. ↑ a b c d e f g h i Lithiophilite . 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; 66  kB ; accessed on June 9, 2019]).
  7. ↑ a b c d Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties. Status 03/2018 . 7th, completely revised and supplemented edition. Weise, Munich 2018, ISBN 978-3-921656-83-9 .
  8. ↑ a b c d e f Lithiophilite. In: mindat.org. Hudson Institute of Mineralogy, accessed June 9, 2019 .
  9. ↑ a b Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp.  622 (first edition: 1891).
  10. ↑ Catalog of Type Mineral Specimens - L. (PDF 69 kB) In: docs.wixstatic.com. Commission on Museums (IMA), December 12, 2018, accessed June 9, 2019 .
  11. ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed June 9, 2019 .
  12. ^ GJ Brush, ES Dana: On a new and remarkable mineral locality in Fairfield County, Connecticut; with a description of several new species occurring there. First paper . In: American Journal of Science and Arts . tape 116 , 1878, pp. 119 (English, rruff.info [PDF; 1.3 MB ; accessed on June 7, 2019]).
  13. ↑ Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason , Abraham Rosenzweig: Dana's New Mineralogy . 8th edition. John Wiley & Sons, New York et al. 1997, ISBN 0-471-19310-0 , pp. 701 .
  14. ↑ Localities for Lithiophilite. In: mindat.org. Hudson Institute of Mineralogy, accessed June 9, 2019 .
  15. ↑ Petr Korbel, Milan Novák: Mineral Encyclopedia (=  Dörfler Natur ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 156 .
  16. ^ Foote Lithium Co. Mine (Foote Mine), Kings Mountain District, Cleveland Co., North Carolina, USA. In: mindat.org. Hudson Institute of Mineralogy, accessed June 12, 2019 .
  17. ^ Lithiophilite pictures of Foote Lithium Co. Mine, Kings Mountain District, Cleveland Co., North Carolina, USA. In: mindat.org. Hudson Institute of Mineralogy, accessed June 12, 2019 .
  18. ↑ Find location list for lithiophilite at the Mineralienatlas and at Mindat