Eveslogite is a complex inosilicate mineral with a

chemical formula In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...

found on Mt. Eveslogchorr in

Khibiny Mountains The Khibiny Mountains (russian: Хиби́ны ; sjd, Umptek) is one of the two main mountain ranges of the Kola Peninsula, Russia, within the Arctic Circle, located between Imandra and Umbozero lakes. The range is also known as Khibiny Massif, K ...

, on the

Kola peninsula sjd, Куэлнэгк нёа̄ррк , image_name= Kola peninsula.png , image_caption= Kola Peninsula as a part of Murmansk Oblast , image_size= 300px , image_alt= , map_image= Murmansk in Russia.svg , map_caption = Location of Murmansk Oblas ...

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

. It was named after the place it was found. This silicate mineral occurs as an anchimonomineral veinlet that cross-cuts poikilitic nepheline

syenite Syenite is a coarse-grained intrusive igneous rock with a general composition similar to that of granite, but deficient in quartz, which, if present at all, occurs in relatively small concentrations (< 5%). Some syenites contain larger proport ...

. This mineral appears to resemble

yuksporite Yuksporite is a rare inosilicate mineral with double width, unbranched chains, and the complicated chemical formula . It contains the relatively rare elements strontium, titanium and niobium, as well as the commoner metallic elements potassium, ...

, as it forms similar placated fine fibrous of approximately 0.05 to 0.005mm that aggregates outwardly. The color of eveslogite is yellow or rather light brown. In addition, it is a semitransparent mineral that has a white streak and a vitreous luster. Its crystal system is monoclinic and possesses a hardness ( Mohs) of 5. This newly discovered mineral belongs to the

astrophyllite Astrophyllite is a very rare, brown to golden-yellow hydrous potassium iron titanium silicate mineral. Belonging to the astrophyllite group, astrophyllite may be classed either as an inosilicate, phyllosilicate, or an intermediate between the two ...

group of

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. ( ...

s and contains structures that are composed of titanosilicate layers (Krivovichev et al., 2004). Limited information about this mineral exists due to the few research studies carried out since its recent discovery.

Introduction

Eveslogite is a

monoclinic In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic s ...

-prismatic mineral that contains a trilogy of elements, which includes:

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has ...

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to ...

barium Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Th ...

chlorine Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate betwee ...

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...

fluorine Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reacti ...

manganese Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy use ...

iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...

niobium Niobium is a chemical element with chemical symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has sim ...

potassium Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

, silicon tantalum, sodium titanium and

zirconium Zirconium is a chemical element with the symbol Zr and atomic number 40. The name ''zirconium'' is taken from the name of the mineral zircon, the most important source of zirconium. The word is related to Persian '' zargun'' (zircon; ''zar-gun'', ...

. It is usually found at Mount Eveslogchorr, Kola Peninsula, Khibina alkaline massif, in Russia. This mineral adds to the rapidly expanding class of the porous materials that are vital in gas separation,

catalysis Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

, optoelectronics, and in ion exchange processes. According to the article Crystal Research and Technology by Depmeier that seeks to further explain the properties of eveslogite, this mineral is in almost all aspect similar to

. However, when compared to yuksporite, eveslogite is much poorer in Ba content and it possesses different thermal capability. This mineral was discovered by Yuri Men’shikov in 1998.

Composition

Eveslogite is a complex titanosilicate made up of numerous elements including

silicon Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic tab ...

sodium Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable iso ...

, calcium and potassium. Its chemical formula is , with the number of atoms in the chemical formula being 298.4. The listed elements in the formula are Ba, Cl, Ca, Fe, F, H, K, Mn, O, Sr, Si and Ti. The table below shows the composition of elements and their relative weight. In addition, this mineral has the empirical formula Ca22.46K12.27Na10.3Sr1.8Ba1.25Ti5.53Nb3.34Mn3+0.95Fe2+0.83Fe3+0.2Zr0.19Rb0.14Ta0.08 (OH)12Si47.3Al0.41O138.08(OH)9.42Cl0.8 and a molecular weight of 6,800.28 grams. Due to this form of composition, eveslogite’s structure has been observed to resist characterization because of its poor

diffraction Diffraction is defined as the interference or bending of waves around the corners of an obstacle or through an aperture into the region of geometrical shadow of the obstacle/aperture. The diffracting object or aperture effectively becomes a s ...

of its crystals and also due to its small dimensions (Chukanov et al., 2008). The aspect of characterization has been made possible after the late 20th century discovery of the 3rd generation X-ray synchrotron sources that made it possible to structurally characterize various mineral elements that could not have been characterized using the in-house X-ray sources (Burzo, 2006).

Physical properties

Eveslogite is a titanosilicate mineral that falls under the group of astrophyllite and fits within the point and space group P2/m . It is a mineral that is light brown or yellowish in color. It has a silky structure with white streak. Its tenacity is brittle and an indistinctly perfect cleavage of and . In regard to its general appearance, as explained by Chukanov et al. 2008, this mineral is indistinguishable from yuksporite and other related titanosilicate. In addition, the article American Mineralogist further expounds on both the measured and calculated densities of this mineral. After measuring the density of eveslogite it recorded a total of 2.85 g/cm3 but when directly calculated, it recorded a slightly higher density of 2.93 g/cm3. Additionally, the physical characteristics of eveslogite include a fracture that is largely splintery and a rough semitransparent gold like appearance.

Structure

The structure of eveslogite is based upon complex rods that consist of the corner sharing octahedral (TiO) and the tetrahedral SiO4. Due to its 5- Apatite hardness and density of 2.85 the general structure of this mineral is a rigid but porous in nature just like other astrophyllite. Some of the minerals that are largely associated with Eveslogite in terms of close similarity of their structure include

nepheline Nepheline, also called nephelite (), is a rock-forming mineral in the feldspathoid groupa silica-undersaturated aluminosilicate, Na3 K Al4 Si4 O16, that occurs in intrusive and volcanic rocks with low silica, and in their associated pegmatites ...

biotite Biotite is a common group of phyllosilicate minerals within the mica group, with the approximate chemical formula . It is primarily a solid-solution series between the iron-endmember annite, and the magnesium-endmember phlogopite; more alumino ...

, fluorite, K-feldspar, eudialyte and also many other minerals that fall under the astrophyllite group. Eveslogite is an orthorhombic mineral that fits within the space group 2lm prismatic. Eveslogite structure of the titanosilicate rods is remarkably unique when compared with other tetrahedral silicates. This is because it consists of a total of nine distinct symmetry independent silicates, which includes; SilO4, Si4O4, and Si5O4 similar to the xonotlite double chains structure. Although eveslogite has a rigid structure, the

nanorod In nanotechnology, nanorods are one morphology of nanoscale objects. Each of their dimensions range from 1–100 nm. They may be synthesized from metals or semiconducting materials. Standard aspect ratios (length divided by width) are 3-5. Na ...

s are porous. These internal pores in the structure of eveslogite are defined by eight-Membered rings (8MR) separated by two parallel channels of Si₉O₄ and Si₄O₇ tetrahedral groups (Krivovichev et al., 2004). On the other hand, the inside part of eveslogite titanosilicate nanorods is composed of

alkali metal The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K),The symbols Na and K for sodium and potassium are derived from their Latin names, ''natrium'' and ''kalium''; these are still the origins of the names ...

s cations Na2,Nal, K1-K5 and the H₂O molecules. In general, the composition of the structure, eveslogite, is especially in the discovery of the existence of titanosilicate nanorods in the composition of this mineral that provides a vital notion for further research and understanding of the structural diversity of Titanosilicate and other alkaline astrophyllite. However, at present, the individual crystal structure of the eveslogite minerals is well described in detail in the article of Geology of Ore Deposits (Chukanov et al. 2008).

Geological occurrence

The particles of eveslogite are found in Mt. Eveslogchorr in

Kola Peninsula sjd, Куэлнэгк нёа̄ррк , image_name= Kola peninsula.png , image_caption= Kola Peninsula as a part of Murmansk Oblast , image_size= 300px , image_alt= , map_image= Murmansk in Russia.svg , map_caption = Location of Murmansk Oblas ...

. In particular the geological occurrence of this mineral and the place of conservation for this mineral is

Fersman Mineralogical Museum ) , native_name = , native_name_lang = , logo = , logo_upright = , logo_alt = , logo_caption = , image = Fersman Mineralogical Museum.JPG , image_upright = , a ...

Moscow Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 million ...

Russia (Hawthorne 2012). Eveslogite derives its name from this locality, particularly from Mt. Evesglochorr. Since it is a newly discovered mineral, there has not been extensive research to show if it occurs in any significant amounts in other parts of the world. Eveslogite often occurs in close proximity with other rare-earth minerals, particularly the other Astrophyllite mineral elements, in addition, intergrowths with particular orientations are frequently found. In regard to its geological setting. Eveslogite is commonly found in peralkaline granitoids, where it may be selectively included by certain major minerals (such as

feldspar Feldspars are a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the ''plagioclase'' (sodium-calcium) feldsp ...

) or may form aggregates of multiple types of other minerals that are also found in the Russian mountain of Eveslogchorr.

Special characteristics

Eveslogite synonym is IMA2001-023 and its axial ratios are; a:b:c =0.5641:1:1.7768. Among its special characteristics is that its estimated radioactivity is barely detectable. The radioactivity test in regard to eveslogite can be measured using GRapi=172.67 (

Gamma Ray A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically ...

American Petroleum Institute The American Petroleum Institute (API) is the largest U.S. trade association for the oil and natural gas industry. It claims to represent nearly 600 corporations involved in production, refinement, distribution, and many other aspects of the pet ...

Units). According to the research carried out by Krivovichev et al., the chemical composition of eveslogite was determined through a wavelength-dispersion spectrometry, which encompasses the Cameca MS-46

microbe A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no kn ...

that was operating at 20kV. This strategy was adopted because of the traditional test of bond lengths and the bond-valence analysis, resulting in errors and therefore could not result in reliable information. Through the use of the wavelength dispersion spectrometry approach, other special feature of the Eveslogite were that, the rods in the structure of the Eveslogite are separated by walls that appears to be parallel and acts as the main linkage of the rods to the 3-dimensional structure of this mineral. This is a special feature to this mineral since other minerals that fall into this Astrophyllite group do not possess these walls in between their rods structure.

References

*Burzo, E. (2006). Neptunite, hellandite, sörensenite, astrophyllite, epididymite, bavenite, lorenzenite and related silicates (Tables). In Inosilicates (pp. 459–468). Springer Berlin Heidelberg. *Chukanov, N. V., Dubovitsky, V. A., Vozchikova, S. A., & Orlova, S. M. (2008). Discrete and functional-geometric methods of infrared spectroscopy of minerals using reference samples. Geology of Ore Deposits, 50(8), 815-826. *Depmeier, W. (2009). Minerals as advanced materials. Crystal Research and Technology, 44(10), 1122-1130. *Hawthorne, F. C. (2012). Who's Who in Mineral Names: Alexander Khomyakov (b. 1933). Rocks & Minerals, 87(6), 555-558. *Krivovichev, S. V., Yakovenchuk, V. N., Armbruster, T., Döbelin, N., Pattison, P., Weber, H. P., & Depmeier, W. (2004). Porous titanosilicate nanorods in the structure of yuksporite, (Sr, Ba) 2K4 (Ca, Na) 14 (□, Mn, Fe){(Ti, Nb) 4 (O, OH) 4 i6O172 i2O73}(H2O, OH) n, resolved using synchrotron radiation. American Mineralogist, 89(10), 1561-1565. Inosilicates Monoclinic minerals Minerals in space group 10