Chemographic exploration of the hyalotekite structure-type

ABSTRACTThe hyalotekite group has been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (memorandum 57–SM/16). The general formula of the minerals of the hyalotekite group may be written as: A2B2M2[Si8T4O28]W where A = Ba2+, Pb2+ or K+; B = Ba2+, Pb2+ or K+; M = Ca2+, Y3+ or REE3+; T = Si4+, B3+ or Be2+; and W = F– or □ (where REE = rare-earth elements and □ = vacancy).Four minerals are currently known in this group: hyalotekite, Ba4Ca2[Si8B2(SiB)O28]F, triclinic, I$\bar 1$; khvorovite, Pb2+4Ca2[Si8B2(SiB)O28]F, triclinic I$\bar 1$; kapitsaite-(Y), Ba4(YCa)[Si8B2B2O28]F, triclinic, I$\bar 1$; and itsiite Ba4Ca2[Si8B4O28]□, tetragonal, I$\bar 4$2m.We explore the possible end-member compositions within this group by conflating the properties of an end-member with the stoichiometry imposed by the bond topology of the hyalotekite structure-type and the crystal-chemical properties of its known constituents. There are two high-coordination sites in the hyalotekite structure, A and B, and occupancy of each of these sites can be determined only by crystal-structure refinement. If these two sites are considered together, there are 19 end-member compositions of the triclinic structure and six end-member compositions of the tetragonal structure involving A and B = Ba2+, Pb2+, K+; M = Ca2+, Y3+, REE3+; and T = Si4+, B3+, Be2+. There is the possibility for many other hyalotekite-group minerals, and two potential new minerals have been identified from data in the literature.

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Crystal chemistry and nomenclature of rhodonite-group minerals

Mineralogical Magazine ◽

10.1180/mgm.2019.65 ◽

2019 ◽

Vol 83 (6) ◽

pp. 829-835 ◽

Cited By ~ 3

Author(s):

Nadezhda V. Shchipalkina ◽

Igor V. Pekov ◽

Nikita V. Chukanov ◽

Cristian Biagioni ◽

Marco Pasero

Keyword(s):

Crystal Chemistry ◽

Structural Formula ◽

Structure Type ◽

Mineral Species ◽

Triclinic Space Group ◽

Space Group ◽

International Mineralogical Association ◽

Mineralogical Association ◽

General Chemical

AbstractThis paper presents the nomenclature of the rhodonite group accepted by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA). An overview of the previous studies of triclinic (space group P$\bar{1}$) pyroxenoids belonging to the rhodonite structure type, with a focus on their crystal chemistry, is given. These minerals have the general structural formula VIIM(5)VIM(1)VIM(2)VIM(3)VIM(4)[Si5O15]. The following dominant cations at the M sites are known at present: M(5) = Ca or Mn2+, M(1–3) = Mn2+; and M(4) = Mn2+ or Fe2+. In accordance with the nomenclature, the rhodonite group consists of three IMA-approved mineral species having the following the general chemical formulae: M(5)AM(1–3)B3M(4)C[Si5O15], where A = Ca or Mn2+; B = Mn2+; and C = Mn2+ or Fe2+. The end-member formulae of approved rhodonite-group minerals are as follows: rhodonite CaMn3Mn[Si5O15]; ferrorhodonite CaMn3Fe[Si5O15]; and vittinkiite MnMn3Mn[Si5O15].

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Classification of the minerals of the graftonite group

Mineralogical Magazine ◽

10.1180/minmag.2017.081.092 ◽

2018 ◽

Vol 82 (6) ◽

pp. 1301-1306 ◽

Cited By ~ 4

Author(s):

Frank C. Hawthorne ◽

Adam Pieczka

Keyword(s):

Crystal Structures ◽

Distinct Species ◽

International Mineralogical Association ◽

Coordination Numbers ◽

Mineralogical Association ◽

Strong Order

ABSTRACTA classification and nomenclature scheme has been approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification for the minerals of the graftonite group. The crystal structures of these minerals have three distinct sites that are occupied by Fe2+, Mn2+and Ca2+. These sites have coordination numbers [8], [5] and [6], and these differences lead to very strong order of Fe2+, Mn2+and Ca2+over these sites. As a result of this strong order, the following compositions have been identified as distinct species: graftonite: FeFe2(PO4)2; graftonite-(Ca): CaFe2(PO4)2; graftonite-(Mn): MnFe2(PO4)2; beusite: MnMn2(PO4)2; and beusite-(Ca): CaMn2(PO4)2.

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Potassic-jeanlouisite from Leucite Hill, Wyoming, USA, ideally K(NaCa)(Mg4Ti)Si8O22O2: the first species of oxo amphibole in the sodium–calcium subgroup

Mineralogical Magazine ◽

10.1180/mgm.2019.38 ◽

2019 ◽

Vol 83 (4) ◽

pp. 587-593

Author(s):

Roberta Oberti ◽

Massimo Boiocchi ◽

Frank C. Hawthorne ◽

Giancarlo Della Ventura ◽

Gunnar Färber

Keyword(s):

Microprobe Analysis ◽

Electron Microprobe Analysis ◽

Structure Refinement ◽

Crystal Structure Refinement ◽

Unit Cell Parameters ◽

X Ray ◽

International Mineralogical Association ◽

Cell Parameters ◽

Mineralogical Association ◽

Sodium Calcium

AbstractPotassic-jeanlouisite, ideally K(NaCa)(Mg4Ti)Si8O22O2, is the first characterised species of oxo amphibole related to the sodium–calcium group, and derives from potassic richterite via the coupled exchange CMg–1W${\rm OH}_{{\rm \ndash 2}}^{\ndash}{} ^{\rm C}{\rm Ti}_1^{{\rm 4 +}} {} ^{\rm W}\!{\rm O}_2^{2\ndash} $. The mineral and the mineral name were approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification, IMA2018-050. Potassic-jeanlouisite was found in a specimen of leucite which is found in the lava layers, collected in the active gravel quarry on Zirkle Mesa, Leucite Hills, Wyoming, USA. It occurs as pale yellow to colourless acicular crystals in small vugs. The empirical formula derived from electron microprobe analysis and single-crystal structure refinement is: A(K0.84Na0.16)Σ1.00B(Ca0.93Na1.02Mg0.04${\rm Mn}_{{\rm 0}{\rm. 01}}^{2 +} $)Σ2.00C(Mg3.85${\rm Fe}_{{\rm 0}{\rm. 16}}^{2 +} $Ni0.01${\rm Fe}_{{\rm 0}{\rm. 33}}^{3 +} {\rm V}_{{\rm 0}{\rm. 01}}^{3 +} $Ti0.65)Σ5.01T(Si7.76Al0.09Ti0.15)Σ8.00O22W[O1.53F0.47]Σ2.00. The holotype crystal is biaxial (–), with α = 1.674(2), β = 1.688(2), γ = 1.698(2), 2Vmeas. = 79(1)° and 2Vcalc. = 79.8°. The unit-cell parameters are a = 9.9372(10), b = 18.010(2), c = 5.2808(5) Å, β = 104.955(2)°, V = 913.1(2) Å3, Z = 2 and space group C2/m. The strongest eight reflections in the powder X-ray pattern [d values (in Å) (I) (hkl)] are: 2.703 (100) (151); 3.380 (87) (131); 2.541 (80) ($\bar 2$02); 3.151 (70) (310); 3.284 (68) (240); 8.472 (59) (110); 2.587 (52) (061); 2.945 (50) (221,$\bar 1$51).

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Structural, chemical and spectroscopic re-examination of type uklonskovite leads to its redefinition

Mineralogical Magazine ◽

10.1180/minmag.2017.081.009 ◽

2017 ◽

Vol 81 (6) ◽

pp. 1397-1404 ◽

Cited By ~ 2

Author(s):

S. Menchetti ◽

L. Bindi ◽

D. Belakovskiy ◽

F. Zaccarini

Keyword(s):

Crystal Structure ◽

Scientific Literature ◽

Careful Analysis ◽

Chemical Formula ◽

International Mineralogical Association ◽

Mineralogical Association ◽

Structural Details ◽

First Time ◽

Shed Light

AbstractThe crystal structure and the chemical composition of uklonskovite from the holotype material was reinvestigated to shed light on its correct chemical formula. On the basis of information gained from this characterization, we revised the formula from NaMg(SO4)OH·2H2O to NaMg(SO4)F·2H2O (F instead of OH). A careful analysis of the structural details together with a critical review of all the chemical data listed in the scientific literature for uklonskovite support our redefinition. We also present Raman data for the mineral for the first time. Our proposal was approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (voting proposal 16-J).

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Lobanovite, K2Na(Fe42+Mg2Na)Ti2(Si4O12)2O2(OH)4, a new mineral of the astrophyllite supergroup and its relation to magnesioastrophyllite

Mineralogical Magazine ◽

10.1180/minmag.2016.080.088 ◽

2017 ◽

Vol 81 (1) ◽

pp. 175-181 ◽

Cited By ~ 8

Author(s):

Elena Sokolova ◽

Fernando Cámara ◽

Frank C. Hawthorne ◽

Evgeny I. Semenov ◽

Marco E. Ciriotti

Keyword(s):

Kola Peninsula ◽

Structure Refinement ◽

New Mineral ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

International Mineralogical Association ◽

Orange Colour ◽

Alkaline Massif ◽

Khibiny Alkaline Massif

AbstractLobanovite, K2Na(Fe42+Mg2Na)Ti2(Si4O12)2O2(OH)4, is a new mineral of the astrophyllite supergroup from Mt. Yukspor, the Khibiny alkaline massif, Kola Peninsula Russia. It has been known previously under the following names: monoclinic astrophyllite, magnesium astrophyllite, magnesiumastrophyllite and magnesioastrophyllite but has never been formally proposed and approved as a valid mineral species by the Commission on new Minerals, Nomenclature and Classification of the International Mineralogical Association. It has now been revalidated and named lobanovite after Dr. Konstantin V. Lobanov, a prominent Russian ore geologist who worked in the Kola Peninsula for more than forty years (Nomenclature voting proposal 15-B). Lobanovite has been described from pegmatitic cavities on Mt. Yukspor where it occurs as elongated bladed crystals, up to 0.04 mm wide and 0.2 mm long, with a straw yellow to orange colour. Associated minerals are shcherbakovite, lamprophyllite, delindeite, wadeite, umbite and kostylevite. Lobanovite is biaxial (–) with refractive indices (λ = 589 nm) α = 1.658, βcalc. = 1.687, γ = 1.710; 2Vmeas. = 81.5– 83°. Lobanovite is monoclinic, space group C2/m, a = 5.3327(2), b = 23.1535(9), c = 10.3775(4) Å, β = 99.615(1)°, V = 1263.3 (1) Å 3, Z = 2. The six strongest reflections in the powder X-ray diffraction data [d (Å), I, (hkl)] are: 3.38, 100, (003); 2.548, 90, (063); 10.1, 80, (001); 3.80, 60, (042,131); 3.079, 50, (132,062); 2.763, 90, (1̄71). The chemical composition of lobanovite was determined by electron-microprobe analysis and the empirical formula (K1.97Ba0.01)∑1.98(Na0.65Ca0.14)∑0.79 (Fe3.182+Mg2.02Na1.00Mn0.72)∑6.92(Ti1.99Nb0.06)∑2.05[(Si8.01Al0.06)∑8.07O24]O2(OH)4.03F0.19 was calculated on the basis of 30.2 (O + OH + F) anions, with H2O calculated from structure refinement, Dcalc. = 3.161 g cm–3. In the structure of lobanovite, the main structural unit is the HOH block, which consists of one close-packed O (Octahedral) and two H (Heteropolyhedral) sheets. The M(1–4) octahedra form the O sheet and the T4O12 astrophyllite ribbons and [5]-coordinated Ti-dominant D polyhedra link through common vertices to form the H sheet. The HOH blocks repeat along [001], and K and Na atoms occur at the interstitial A and B sites. The simplified and end-member formulae of lobanovite are K2Na [(Fe2+,Mn)4Mg2Na]Ti2(Si4O12)2O2(OH)4 and K2Na(Fe42+Mg2Na)Ti2(Si4O12)2O2(OH)4, respectively.

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Recommended nomenclature for zeolite minerals: report of the subcommittee on zeolites of the International Mineralogical Association, Commission on New Minerals and Mineral Names

Mineralogical Magazine ◽

10.1180/002646198547800 ◽

1998 ◽

Vol 62 (04) ◽

pp. 533-571 ◽

Cited By ~ 52

Author(s):

Douglas S. Coombs ◽

Alberto Alberti ◽

Thomas Armbruster ◽

Gilberto Artioli ◽

Carmine Colella ◽

...

Keyword(s):

Structure Type ◽

Group Symmetry ◽

Mineral Species ◽

Separate Species ◽

Tetrahedral Framework ◽

International Mineralogical Association ◽

Mineralogical Association ◽

Working Definition ◽

Definition Of ◽

Compositional Series

Abstract This report embodies recommendations on zeolite nomenclature approved by the International Mineralogical Association Commission on New Minerals and Mineral Names. In a working definition of a zeolite mineral used for this review, interrupted tetrahedral framework structures are accepted where other zeolitic properties prevail, and complete substitution by elements other than Si and Al is allowed. Separate species are recognized in topologically distinctive compositional series in which different extra-framework cations are the most abundant in atomic proportions. To name these, the appropriate chemical symbol is attached by a hyphen to the series name as a suffix except for the names harmotome, pollucite and wairakite in the phillipsite and analcime series. Differences in spacegroup symmetry and in order—disorder relationships in zeolites having the same topologically distinctive framework do not in general provide adequate grounds for recognition of separate species. Zeolite species are not to be distinguished solely on Si : Al ratio except for heulandite (Si : Al < 4.0) and clinoptilolite (Si : Al ⩾ 4.0). Dehydration, partial hydration, and over-hydration are not sufficient grounds for the recognition of separate species of zeolites. Use of the term ‘ideal formula’ should be avoided in referring to a simplified or averaged formula of a zeolite. Newly recognized species in compositional series are as follows: brewsterite-Sr, -Ba; chabazite-Ca, - Na, -K; clinoptilolite-K, -Na, -Ca; dachiardite-Ca, -Na; erionite-Na, -K, -Ca; faujasite-Na, -Ca, -Mg; ferrierite-Mg, -K, -Na; gmelinite-Na, -Ca, -K; heulandite-Ca, -Na, -K, -Sr; levyne-Ca, -Na; paulingite-K, -Ca; phillipsite-Na, -Ca, -K; stilbite-Ca, -Na. Key references, type locality, origin of name, chemical data, IZA structure-type symbols, space-group symmetry, unit-cell dimensions, and comments on structure are listed for 13 compositional series, 82 accepted zeolite mineral species, and three of doubtful status. Herschelite, leonhardite, svetlozarite, and wellsite are discredited as mineral species names. Obsolete and discredited names are listed.

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Mesaite, (V2O7)3·12H2O, a new vanadate mineral from the Packrat mine, near Gateway, Mesa County, Colorado, USA

Mineralogical Magazine ◽

10.1180/minmag.2016.080.095 ◽

2017 ◽

Vol 81 (2) ◽

pp. 319-327 ◽

Cited By ~ 1

Author(s):

Anthony R. Kampf ◽

Barbara P. Nash ◽

Joe Marty ◽

John M. Hughes

Keyword(s):

Powder Diffraction ◽

New Mineral ◽

Formula Unit ◽

International Mineralogical Association ◽

Mineralogical Association ◽

Interlayer Region ◽

Perfect Cleavage ◽

Mohs Hardness ◽

Measured Density

AbstractMesaite (IMA2015-069), ideally (V2O7)3·12H2O, is a new mineral from the Packrat mine, Gateway district, Mesa County, Colorado, USA. Crystals of mesaite occur as orangish red blades up to 0.1 mm long and ∼10 μm thick. The streak is light pinkish orange and the lustre is vitreous, transparent. Mesaite has a brittle tenacity, {010} perfect cleavage; fracture is irregular, and no parting was observed. The mineral has a Mohs hardness ≈ 2. The measured density of mesaite is 2.74(1) g cm–3. Mesaite is biaxial (–), α = 1.760(calc), β = 1.780(5), γ = 1.795(5) in white light; the measured 2V value = 81(2)°. Dispersion is strong, r < v, and pleochroism is present in shades of brownish orange. Mesaite is monoclinic, P2/n, with a = 9.146(2), b = 10.424(3), c = 15.532(4) Å, β = 102.653(7)° and V = 1444.7(6) Å3. The strongest four diffraction lines in the powder diffraction pattern are [(dobs in Å, (Iobs), (hkl)]: 10.47 (100) (010), 2.881 (25) (132, 3̄12, 033, 310), 3.568 (24) (1̄14, 1̄23, 2̄13), 3.067 (17) (1̄24, 1̄32, 2̄23). The composition of mesaite was determined by electron microprobe, and yielded an empirical formula of Mn5.32Ca0.56Zn0.31V5.96As0.04O33H23.61 on the basis of 33 O atoms per formula unit (apfu).The atomic arrangement of mesaite was solved and refined to R1 = 0.0600. The structure is formed of zigzag octahedral chains of edge-sharing Mn2+O6 octahedra. Oxygen atoms of the octahedra are shared with V2O7 groups, which link with adjacent octahedral chains to form {010} heteropolyhedral layers. The interlayer region contains Ca atoms and H2O groups. Each Ca bonds to two O6 atoms in the heteropolyhedral layer and to two fully occupied and six partially occupied O (H2O) sites in the interlayer, resulting in an effective Ca coordination of approximately seven. Similar zigzag chains of edge-sharing MnO6 octahedra decorated with V2O7 groups are also found in the mineral fianelite. Mesaite has beenapproved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA2015-069). The name mesaite is conferred for Mesa County, Colorado, USA.

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Review of tetrahedrites from Bulgarian deposits in the light of changes in nomenclature and classification of these minerals taken in 2019

Review of the Bulgarian Geological Society ◽

10.52215/rev.bgs.2020.81.1.1 ◽

2020 ◽

Vol 81 (1) ◽

pp. 3-15

Author(s):

Vladislav Kostov-Kytin

Keyword(s):

Spatial Distribution ◽

Chemical Composition ◽

Electron Probe ◽

Mineral Species ◽

Published Data ◽

Crystal Chemical ◽

International Mineralogical Association ◽

Mineralogical Association ◽

Chemical Trends

The crystal-chemical peculiarities of the minerals in the tetrahedrite group are considered as a prerequisite for their role as indicators of the formation environment. Particular attention is paid to the silver-containing representatives because they comprise more than 60% of the Bulgarian tetrahedrites and because the recently adopted by the International Mineralogical Association changes in the nomenclature and classification within this group affect most sensitively them and their relation to a given series, mineral species or variety. The achievements of the Bulgarian mineralogical science in the study of tetrahedrites are briefly presented, and various aspects are considered, illustrating the efforts of the researchers to cover the diversity of these minerals as well as the opportunity to derive from this various crystal-chemical, geochemical and other mineralogical information. In the light of the adopted changes, already published data from 450 electron-probe microanalyses of samples from 45 localities distributed in three metallogenic zones in the country have been processed. The established crystal-chemical trends in the spatial distribution of tetrahedrites in Bulgaria generally confirm and extend the observations of previous researchers. It has been shown that, by their chemical composition, these minerals can be carriers of typomorphic characteristics, both for individual deposits and for metallogenic zones. The information and data provided may serve to: (i) correctly determine the mineral species of the newly investigated tetrahedrites and their affiliation to a given series; (ii) what compositions may be sought or expected according to the location of the investigated localities; (iii) comparing the new results to previous ones to confirm, correct or reject established models and trends.

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A comment on “An evolutionary system of mineralogy: Proposal for a classification of planetary materials based on natural kind clustering”

American Mineralogist ◽

10.2138/am-2021-7590 ◽

2021 ◽

Vol 106 (1) ◽

pp. 150-153

Author(s):

Frédéric Hatert ◽

Stuart J. Mills ◽

Frank C. Hawthorne ◽

Mike S. Rumsey

Keyword(s):

Mineral Species ◽

New Mineral ◽

Evolutionary System ◽

Species Classification ◽

Classification Schemes ◽

International Mineralogical Association ◽

Mineralogical Association ◽

New Mineral Species ◽

Planetary Materials

Abstract The classification and nomenclature of mineral species is regulated by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMACNMNC). This mineral species classification is necessary for Earth Sciences, as minerals constitute most planetary and interstellar materials. Hazen (2019) has proposed a classification of minerals and other Earth and planetary materials according to “natural clustering.” Although this classification is complementary to the IMA-CNMNC mineral classification and is described as such, there are some unjustified criticisms and factual errors in the comparison of the two schemes. It is the intent of the present comment to (1) clarify the use of classification schemes for Earth and planetary materials, and (2) counter erroneous criticisms or statements about the current IMA-CNMNC system of approving proposals for new mineral species and classifications.

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Tsikourasite, Mo3Ni2P1+x (x < 0.25), a New Phosphide from the Chromitite of the Othrys Ophiolite, Greece

Minerals ◽

10.3390/min9040248 ◽

2019 ◽

Vol 9 (4) ◽

pp. 248 ◽

Cited By ~ 4

Author(s):

Zaccarini ◽

Bindi ◽

Ifandi ◽

Grammatikopoulos ◽

Stanley ◽

...

Keyword(s):

Empirical Formula ◽

Polarized Light ◽

Average Composition ◽

Synthetic Compound ◽

Space Group ◽

International Mineralogical Association ◽

Mineralogical Association ◽

Brunei Darussalam ◽

Podiform Chromitite

Tsikourasite, Mo3Ni2P1+x (x < 0.25), is a new phosphide discovered in a mantle-hosted podiform chromitite collected in the abandoned mine of Agios Stefanos (Othrys ophiolite), Central Greece. It forms tiny grains (from a few μm up to about 80 μm) and occurs as isolated grains or associated with other known minerals such as nickelphosphide and awaruite, and with undetermined minerals such as Ni-allabogdanite or Ni-barringerite and a V-sulphide. Tsikourasite is brittle and has a metallic luster. In plane-polarized light, tsikourasite is white yellow and it shows no bireflectance, anisotropism or pleochroism. Internal reflections were not observed, Reflectance values of tsikourasite in air (R in %) are: 55.7 at 470 nm, 56.8 at 546 nm, 57.5 at 589 nm and 58.5 at 650 nm. Five spot analyses of tsikourasite give the average composition: P 7.97, S 0.67, V 14.13, Fe 14.37, Co 7.59, Ni 23.9, and Mo 44.16, total 99.60 wt%, corresponding to the empirical formula (Mo1.778V1.071Fe0.082Co0.069)Σ3.000(Ni1.572Co0.428)Σ2.000(P0.981S0.079)Σ1.060, on the basis of Σ(Mo +V + Fe + Co + Ni) = 5 apfu and taking into account the structural results. The simplified formula is Mo3Ni2P1+x (x < 0.25). The density, which was calculated based on the empirical formula and single-crystal data, is 9.182 g/cm3. The mineral is cubic, space group F-43m, with a = 10.8215(5) Å and Z = 16. Although tsikourasite is similar in composition to those of monipite (MoNiP), polekhovskyite (MoNiP2), and the synthetic compound MoNiP2, all these phases are hexagonal and not cubic like tsikourasite. It exhibits the same structure as the cubic Mo3Ni2P1.18 compound [space group F-43m, a = 10.846(2) Å] synthesized at 1350 °C. The mineral and its name have been approved by the Commission of New Minerals, Nomenclature and Classification of the International Mineralogical Association (No. 2018-156). The mineral honors Professor Basilios Tsikouras of the Universiti Brunei Darussalam.

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