Mineral Names Research Articles

Eliopoulosite, V7S8, A New Sulfide from the Podiform Chromitite of the Othrys Ophiolite, Greece

The new mineral species, eliopoulosite, V7S8, was discovered in the abandoned chromium mine of Agios Stefanos of the Othrys ophiolite, located in central Greece. The investigated samples consist of massive chromitite hosted in a strongly altered mantle tectonite, and are associated with nickelphosphide, awaruite, tsikourasite, and grammatikopoulosite. Eliopoulosite is brittle and has a metallic luster. In plane-reflected polarized light, it is grayish-brown and shows no internal reflections, bireflectance, and pleochroism. It is weakly anisotropic, with colors varying from light to dark greenish. Reflectance values of mineral in air (Ro, Re’ in %) are: 34.8–35.7 at 470 nm, 38–39 at 546 nm, 40–41.3 at 589 nm, and 42.5–44.2 at 650 nm. Electron-microprobe analyses yielded a mean composition (wt.%) of: S 41.78, V 54.11, Ni 1.71, Fe 1.1, Co 0.67, and Mo 0.66, totali 100.03. On the basis of Σatoms = 15 apfu and taking into account the structural data, the empirical formula of eliopoulosite is (V6.55Ni0.19Fe0.12Co0.07Mo0.04)Σ = 6.97S8.03. The simplified formula is (V, Ni, Fe)7S8 and the ideal formula is V7S8, which corresponds to V 58.16%, S 41.84%, total 100 wt.%. The density, based on the empirical formula and unit-cell volume refined form single-crystal structure XRD data, is 4.545 g·cm−3. The mineral is trigonal, space group P3221, with a = 6.689(3) Å, c = 17.403(6) Å, V = 674.4(5) Å3, Z = 3, and exhibits a twelve-fold superstructure (2a × 2a × 3c) of the NiAs-type subcell with V-atoms octahedrally coordinated by S atoms. The distribution of vacancies is discussed in relation to other pyrrhotite-like compounds. The mineral name is for Dr. Demetrios Eliopoulos (1947–2019), a geoscientist at the Institute of Geology and Mineral Exploration (IGME) of Greece and his widow, Prof. Maria Eliopoulos (nee Economou, 1947), University of Athens, Greece, for their contributions to the knowledge of ore deposits of Greece and to the mineralogical, petrographic, and geochemical studies of ophiolites, including the Othrys complex. The mineral and its name have been approved by the Commission of New Minerals, Nomenclature, and Classification of the International Mineralogical Association (No. 2019-96).

Who's Who in Mineral Names: Jacobus “Jaco” Stephanus Janse van Nieuwenhuizen (b. 1973) and Tania Janse van Nieuwenhuizen (b. 1973)

Lucas Becker photo.Taniajacoite, SrCaMn23+Si4O11(OH)4·2H2O, is triclinic and a member of the ruizite group; it is named for husband and wife Tania and Jacobus van Nieuwenhuizen* who discovered the ...

The Where of Mineral Names: Karibibite, Karibib District, Namibia

Karibibite, Fe33+(As3+O2)4(As23+O5)(OH), was described from a pegmatite in the Karibib district of Namibia by von Knorring, Sahama, and Rehtijarvi (1973). Their description of the type material, ho...

New Mineral Names*,†

In this issue This New Mineral Names has entries for 11 new minerals, including cesiodymite, cryptochalcite, feodosiyite, fluoro-tremolite, itelmenite, ozerovaite, ramazzoite, redcanyonite, selivanovite, vanderheydenite, and wrightite.

Who's Who in Mineral Names: Tucsonan Ronald Bradford Gibbs (b. 1949)

Who's Who in Mineral Names: Tucsonan Ronald Bradford Gibbs (b. 1949)

Optical, structural, morphological, and compositional properties of cobalt doped tin oxide (CTO) thin films deposited by modified chemical bath method in alkaline medium

Tin oxide and cobalt doped tin oxide (CTO) thin films were successfully deposited using modified chemical bath method with tin (II) chloride dihydrate and cobalt chloride hexahydrate as precursors for Sn and Co ions respectively, in the presence of ammonium hydroxide as source of oxygen and pH adjuster. The samples obtained were annealed for 4 h at a temperature of 673 K and characterized for optical, structural, morphological and compositional analysis. The films exhibit low absorbance values (0.02–0.31) and low reflectance values (2.14%–20.10%) which varies directly with cobalt ion (Co2+) concentration. The transmittance values (48.64%–96.16%) of the films are high and varies inversely with cobalt ion (Co2+) concentration. The refractive index varies directly with increasing cobalt ion concentration and ranges from 2.60 to 1.49 for doped film and 1.34 for the undoped SnO2. Extinction coefficient of the films varies directly with cobalt ion concentration. The films have wide band gap, (2.90 eV–2.72 eV for doped films and 3.05 eV for undoped SnO2 thin film). Structural analysis revealed that the films are of tetragonal rutile phase of SnO2 with mineral name of cassiterite and confirmed that the grain sizes of the deposited films range from 10.99 nm to 9.40 nm. The dislocation density ranged between 8.28×10−3(line/nm2) and 11.32×10−3(line/nm2) while the microstrain obtained ranged between 6.07×10−3 to 12.03×10−3. The compositional results revealed the presence of the Sn, Co, O2 and some traces of other elements. The SEM images obtained show uniform surface without any voids or flaws. The micrographs show that the surfaces are composed of particles of slightly different sizes.

Nipalarsite, Ni8Pd3As4, a new platinum-group mineral from the Monchetundra Intrusion, Kola Peninsula, Russia

AbstractNipalarsite, Ni8Pd3As4, is a new platinum-group mineral discovered in the sulfide-bearing orthopyroxenite of the Monchetundra layered intrusion, Kola Peninsula, Russia (67°52′22″N, 32°47′60″E). Nipalarsite forms anhedral grains (5–80 µm in size) in intergrowths with sperrylite, kotulskite, hollingworthite, isomertieite, menshikovite, palarstanide, nielsenite and monchetundtraite enclosed in pentlandite, anthophyllite, actinolite and chlorite. Nipalarsite is brittle, has a metallic lustre and a grey streak. In plane-polarised light, nipalarsite is light grey with a blue tinge. Reflectance values in air (in %) are: 46.06 at 470 nm, 48.74 at 546 nm, 50.64 at 589 nm and 54.12 at 650 nm. Values of VHN20 fall between 400.5 and 449.2 kg.mm–2, with a mean value of 429.9 kg.mm–2, corresponding to a Mohs hardness of ~4. The average result of 27 electron microprobe wavelength dispersive spectroscopy analyses of nipalarsite is (wt.%): Ni 44.011, Pd 28.74, Fe0.32, Cu 0.85, Pt 0.01, Au 0.05, As 25.42, Sb 0.05, Te 0.39, total 99.85. The empirical formula (normalised to 15 atoms per formula unit) is: (Ni8.10Fe0.06)Σ8.16(Pd2.94Cu0.18)Σ3.12(As3.68Te0.03)Σ3.71 or, ideally, Ni8Pd3As4. Nipalarsite is cubic, space group Fm$\bar{3}$m, with a = 11.4428(9) Å, V = 1498.3(4) Å3 and Z = 8. The strongest lines in the powder X-ray diffraction pattern of synthetic Ni8Pd3As4 [d, Å (I) (hkl)] are: 2.859(10)(004), 2.623(6)(313), 2.557(6)(024), 2.334(11)(224), 2.201(35)(115,333), 2.021(100)(044), 1.906(8)(006,244) and 1.429(7)(008). The crystal structure was solved and refined from the single-crystal X-ray diffraction data of synthetic Ni8Pd3As4. The relation between natural and synthetic nipalarsite is illustrated by an electron back-scattered diffraction study of natural nipalarsite. The density calculated on the basis of the empirical formula of nipalarsite is 9.60 g.cm–3. The mineral name corresponds to the three main elements: Ni, Pd and As.

Calorimetric measurements of sodium chloride dihydrate (hydrohalite)

Calorimetric measurements of sodium chloride dihydrate NaCl·2H2O (mineral name hydrohalite) were carried out with using DSC. Heat capacity from 190 to 250 K was measured and found to increase from 109 to 137 J mol−1 K−1. The enthalpy of formation of hydrohalite from solid ice and halite at 273.15 K was derived from the thermal effect of melting/decomposition in DSC measurements and found to be close to − 1.8 kJ mol−1. The same DSC results show clearly that the upper temperature limit for the existence of hydrohalite is several degrees greater than the current value of 273.15 K accepted for the peritectic decomposition of hydrohalite. The phase diagram of the NaCl–H2O system needs correction.

Who's Who in Mineral Names: Eugene “Gene” Stuart Meieran (b. 1937)

Who's Who in Mineral Names: Eugene “Gene” Stuart Meieran (b. 1937)

New Mineral Names*,†

In this issue This New Mineral Names has entries for 9 new minerals, including argentotetrahedrite-(Fe), bytízite, calamaite, fluorlamprophyllite, honzaite, katerinopoulosite, meitnerite, melcherite, and rozhdestvenskayaite-(Zn).

Difference in Oxide Ion Conduction Properties of Oxide Ion Excess and Cation Deficient PbWO4s and Oxide Ion Deficient CaWO4

Introduction When lanthanum ions are partly substituted for lead in PbWO4 with sheelite-type structure, high oxide ion conduction appeared at elevated temperature [1]. From the density measurement, it has been reported that oxide ion interstitials are formed for the substitution as Pb1-xLaxWO4+x/2, while Pb1-xLa2/3WO4 shows the defect structure of cation deficiency. While the former system exhibits a little higher oxide ion conduction, both systems show approximately unity of the oxide ion transport number. In recent years, it is also found that CaWO4 with the mineral name of scheelite also exhibit the oxide ion conduction by partly substituting potassium ions for calcium site as Ca1-xKxWO4-x/2. In addition to the electrochemical measurements, we have investigated the high-temperature neutron diffraction on these experiments to clarify the oxide ion conduction paths at high-temperatures. We have reported these results separately and have not compared with concerning defect structure. In the present study, we compare the conduction paths between three types of scheelite-type structured oxide ion conductors from the results of high-temperature neutron diffraction. Experimental Pb1-xLaxWO4+x/2 (x = 0.2), while Pb1-xLa2/3WO4 (x = 0.1) and Ca1-xKxWO4-x/2 (x = 0.2) were prepared by conventional solid-state reaction method started from PbO, La2O3, H2WO4, CaCO3 and K2CO3. The sintering temperatures were selected as 900ºC for PbWO4-based materials and 1000ºC for CaWO4s. The crystalline phase of the obtained samples was confirmed by X-ray diffraction. The sintered samples with the amount of c.a. 10 g are set into a vanadium holder with a thin quartz tube to prevent the reaction of sample with holder, which was mounted to the neutron diffractometer SHRPD in J-PARC. Diffracted neutrons were collected at various temperatures up to 800ºC. Structure analyses were performed by using Z-Rietveld, and the trace of nuclear density was calculated by Z-MEM. BVS calculations were also carried out based on the refined structure data. Results and Discussions Fig. 1 exhibits the nuclear density map of (a) Pb1-xLaxWO4+x/2, (b) Pb1-xLa2/3WO4 and (c) Ca1-xKxWO4-x/2 deduced by maximum entropy method based on the neutron diffraction data collected at 800ºC. For Pb1-xLaxWO4+x/2 with the oxide ion interstitials, nuclear density seems to be distributed to the interstitial site, while the latter two systems without oxide ion interstitials, much less amount of nuclear density is observed at the interstitial sites. Therefore, Pb1-xLaxWO4+x/2 system possess the three-dimensional conduction path allowing higher oxide ion conductivity at elevated temperatures. We will also discuss the conduction path in terms of the bond valence sum.

Automated SEM Mineral Liberation Analysis (MLA) with Generically Labelled EDX Spectra in the Mineral Processing of Rare Earth Element Ores

Many rare earth element (REE) deposits have experienced multistage geological enrichment processes resulting in REE bearing mineral assemblages of considerable complexity and variability. Automated scanning electron microscopy (SEM) mineral liberation analysis of such REE ores is confronted by the difficult assignment of energy-dispersive X-ray (EDX) spectra to REE mineral names. To overcome and bypass this problem, a generic and reliable labelling of EDX reference spectra obtained from REE-bearing minerals based on their contents of Si, Ca, F and P in a bulk normalised analysis is proposed. The labelled spectra are then combined into groups of REE-P (~monazite), REE-Ca-Si-P (~britholite), REE-Ca-F (~synchysite) and REE-F (~bastnaesite, parisite, fluocerite). Mixed spectra with low counts for REE from minute REE mineral grains are combined into a separate group. This classification scheme is applied to automated SEM mineral liberation analysis (MLA) data from beneficiation products by comminution and multistage flotation of REE carbonatite ores. Mineral modes, mineral grain size distribution, mineral liberation, mineral locking and mineral grade versus recovery curves based on the analysis of >200,000 particles in a sample can be recognised and interpreted in virtual grain size fractions. The approach as proposed here will allow future process mineralogical studies of REE deposits to be robust and comparable.

Who's Who in Mineral Names: Roy McGillivray Miller (b. 1941)

Roymillerite, Pb24Mg9(Si9AlO28)(SiO4)(BO3)(CO3)10(OH)14O4, is chemically and structurally related to britvinite and molybdophyllite and was discovered in a lead-rich assemblage of minerals from the...

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

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).

Digitisation of Geocollections and the New Generation of Curators

Digital inventory of collections is one of the main priorities of curatorship work at museums. In the Science Museum of the University of Coimbra these process started in 2007 with the development of the Virtual Museum project reaching 9,000 digitised specimens of Natural History. The public access to the information via the museum webpage increased the impact of the museum collections for the public and for the scientific and museum communities in Portugal and abroad. The number of loans for exhibitions and research visitors has grown exponentially. The Portuguese Museology Association (APOM) prized the former domain http://museudaciencia.inwebonline.net/ in 2010 with the Best Implementation and Multimedia Managment. Since 2007 the Museum has been improving its facilities and human resources and a new generation of curators and assistant curators are getting involved. Nevertheless, a substantial part of this new generation has been maintained by fellowships associated to time-limited projects, resulting in an inevitable gap of continuity. An infrastructure project is currently developing at the museum, the PRISC consortium (Portuguese Research Infrastructure of Scientific Collections). It consists of an e-infrastructure providing the services to the collections with special emphasis in the human resources curatorship. In the case of the geocollections this represents the filling of an almost one decade gap of no collection digitisation activity. The geocollections are the second largest archive of specimens and associated data of the museum, reaching an estimated amount of more than 30,000 specimens. It comprises Mineralogy, Petrology and Palaeontology specimens and is one of the largest and oldest Portuguese geodiversity repositories. The online portal is fed by the information stored in a database that is steadily growing with new incoming specimens, 2D images, and data from the transcription of relevant label records and old catalogues. That process is crucial to promote the best-practice systems for collection management. Geocollections have specific requirements comparing to other Natural History collections and dedicated thesaurus are mandatory to accommodate the related data. That process has been developed in many cases by feeding the data to the database but in other cases forced to reprogramme new fields in it. The terminology associated with the specimens, such as lithostratigraphy units, chronostratigraphic terms, or regional rock and mineral names are frequently out of date and should be readjusted to the internationally accepted names. This is one of the cases that evidences how important it is to improve good practice initiatives to normalize the data. Most of the Museum´s databases are feeding global data-sharing utilities such as Global Biodiversity Information Facility (GBIF) or The Encyclopedia of Life (EOL). This global sharing of data claims important data quality and standardization implementation practices. In order to fulfill that goal, a new generation of curators is being prepared with skills in a logic of networking. The involvement and enthusiasm of these young generations of curators is at the base of a quality curatorship in today’s museums.

Who's Who in Mineral Names: Robert François Martin (b. 1941)

Who's Who in Mineral Names: Robert François Martin (b. 1941)

Gaildunningite, Ideally Hg2+3[NHg2+2]18(Cl,I)24, a New Mineral from the Clear Creek Mine, San Benito County, California, USA: Description and Crystal Structure

Gaildunningite, ideally Hg-3(2+)[NHg22+](18)(Cl,I)(24), is a new mineral from the Clear Creek mine, New Idria mining district, San Benito County, California, USA. It is orthorhombic, space group Amam, Z 1/4 4; a 26.381(6), b 45.590(10), c 6.6840(15) angstrom, V 8039(5) angstrom(3). Chemical analysis by electron microprobe gave Hg 76.87, I 12.55, Cl 3.79, Br 0.56, S 0.18 wt.%; N 2.45, O 0.28, and H 0.02 wt.% were derived from the crystal structure to give a total of 96.70 wt.%. The empirical formulae (calculated on the basis of 39.44 Hg with 18 N and OH added to give electroneutrality) is Hg39.442+N18[Cl11.00I10.18(OH)(1.81)Br0.73S0.58](Sigma 24.30) and the simplified formula is Hg-3(2+)[NHg22+](18)(Cl,I)(24). The seven strongest lines in the X-ray powder diffraction pattern [listed as d (angstrom), I, (hkl)] are as follows: 2.853, 100, (880, 0.16.0); 2.776, 100, (462, 5.14.0); 2.745, 100, (542); 5.717, 50, (440, 080); 5.965, 40, (131); 5.018, 40, (331); 1.673, 40, (004). Gaildunningite generally forms complex parallel intergrowths of fibrous to acicular crystals elongated along [001]. Acicular yellow to orange to darker orange-red crystals up to 0.1 mm long form matted nests lining vugs within white-grey quartz. Gaildunningite has a vitreous to adamantine luster, is transparent, and does not fluoresce under short-or long-wave ultraviolet light. Mohs hardness approximate to 3 and the calculated density is 8.22 g/cm(3). It is brittle with an uneven fracture and has very good cleavage on {100} and {010} and good cleavage on {001}; neither parting nor twinning was observed. It is grey in reflected light with possibly minor bireflectance but no reflectance pleochroism, and strong yellow-orange internal reflections are evident even in plane-polarized light. The Raman spectrum indicates the presence of Hg-N bonds in the structure. The crystal structure of gaildunningite is based on a well-ordered three-dimensional [NHg2](+) net of near-linear N-Hg-N groups, where each N3- is tetrahedrally coordinated by Hg2+. The net is comprised of two five-membered, three six-membered, one seven-membered, and one eight-membered rings of N-Hg-N groups. The interstitial part of the structure is significantly disordered and consists of (Hg2+) and (I-, Cl-, Br-, S2-, OH-) ions. A new bond-valence parameter has been derived for (Hg2+-N3-) bonds: R-o = 1.964 angstrom, b 1/4 0.37; this gives bond-valence sums at the N3- ions in accord with the valence-sum rule.Gaildunningite and unnamed CCUK-18 are the only (Hg-N-I)-bearing minerals discovered at Clear Creek to date and are closely associated; gaildunningite is the later of these two minerals and tends to grow on CCUK-18. They post-date the iodine-free nitride mosesite and the (N, I)-free chlorides such as eglestonite, implying that iodine was a late addition to the overall chemical system. Both the mineral and the mineral name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA 2018-029). The mineral is named after Gail E. Dunning (b. 1937), a prominent field-collector of minerals from the New Idria mining district who has been responsible for the discovery of many new mercury-bearing minerals.

Discreditation of the pyroxenoid mineral name ‘marshallsussmanite’ with a reinstatement of the name schizolite, NaCaMnSi3O8(OH)

AbstractSchizolite, originating from the type locality, Tutop Agtakôrfia, in the Ilímaussaq alkaline complex, Julianehåb district, South Greenland, was described initially by Winther (1901) with additional data being supplied by Bøggild (1903). Recently, a proposal for the new mineral ‘marshallsussmanite’ was submitted to, and approved by, the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification (IMA2013-067) by Origlieri et al. (2013). Results from the detailed examination of two schizolite cotype samples presented here, using single-crystal and powder X-ray diffraction, and optical properties, confirms it to be equivalent to ‘marshallsussmanite’. Historical precedence sets a priority for discrediting the name ‘marshallsussmanite’ in favour of the original, more-than-a century-old name, schizolite. The two schizolite samples investigated vary slightly in physical and chemical properties but are consistent overall. The prismatic crystals are pale red or pink to brownish. Schizolite is brittle with a splintery aspect. It is biaxial (+), with average optical parameters: α = 1.626 ± 0.003, β = 1.630 ± 0.002, γ = 1.661 ± 0.002, 2Vmeas = 71(4)° and 2Vcalc = 40°; there is no pleochroism. Electron microprobe analysis shows both samples have nearly identical compositions (differences <0.4 wt.% oxide), with the mean values of: SiO2 52.6(4); Al2O3 0.005(1); FeO 2.54(2); MnO 13.86(9); CaO 17.9(4); Na2O 8.9(1); and H2O 2.59(2) wt.% oxide; this corresponds to a mean formula of: Na1.00(2)Ca1.11(7)Mn0.68(1)Fe0.12(0)Si3.041(1)O8(OH). Final least-squares structure refinements for both samples converged at R1 values ≤2.0%; H atoms were located in all refinements.

Who's Who in Mineral Names: Michael “Mike” Scott Rumsey (b. 1980)

Rumseyite, [Pb2OF]Cl, is a very rare lead fluoroxychloride, discovered in 2011 in specimen material from the Torr Works quarry (better known to many collectors by its former name of Merehead quarry...

The Where of Mineral Names: Gamagarite, Gloucester Mine, Gamagara Hills, Postmasburg Manganese and Iron-Ore Field, South Africa

The Postmasburg manganese and iron-ore field (Gutzmer and Beukes 1996; Cairncross, Beukes, and Gutzmer 1997) might be considered the poorer relative to its northerly neighbor, the Kalahari manganes...