Zhenruite, (MoO 3 ) 2 ⋅ H 2 O, and tianhuixinite, (MoO 3 ) 3 ⋅ H 2 O, two new minerals in the MoO 3 –MoO 3 ⋅ 2H 2 O system

A new mineral species, raydemarkite, ideally MoO3·H2O, was discovered in an unnamed short adit on the Summit group of claims near Cookes Peak, Luna County, New Mexico, USA. It occurs as sprays of acicular or prismatic crystals on a matrix consisting mainly of quartz and pyrite. Individual crystals of raydemarkite are up to 1.00 × 0.10 × 0.06 mm. Associated minerals include sidwillite, ilsemannite, jordisite, powellite, anhydrite, gypsum, bouškaite, pyrite, and quartz. Raydemarkite is colorless in transmitted light and transparent with white streak and vitreous luster. It is flexible and has a Mohs hardness of ∼1½; cleavage is perfect on {100} and {001}. Twinning is common on (010). The measured and calculated densities are 3.44(5) and 3.41 g/cm3, respectively. Raydemarkite is insoluble in water or hydrochloric acid. An electron microprobe analysis yielded an empirical formula, based on 4 O apfu, of MoO3·H2O.Raydemarkite is the natural analogue of the α-form of MoO3·H2O, which was first synthesized over a century ago (Rosenheim & Davidsohn 1903). Its crystal structure was solved using single-crystal X-ray diffraction data. It is triclinic, crystallizing in space group and the unit-cell parameters a = 7.3750(2), b = 3.70920(10), c = 6.6833(2) Å, α = 108.1080(10), β = 112.779(2), γ = 91.7420(10)°, V = 157.828(8) Å3, and Z = 2. The crystal structure of raydemarkite is built up from isolated double chains of highly distorted, edge-sharing MoO5(H2O) octahedra parallel to [010] that are linked together through hydrogen bonds, accounting for its acicular/prismatic morphology and the marked flexibility. Synthetic hemihydrate MoO3·1/2H2O (monoclinic, space group P21/m) can be regarded as a combination of molybdite and raydemarkite both structurally and chemically.

The new mineral virgilluethite, ideally β-MoO3·H2O, was discovered in an unnamed short adit on the Summit group of claims near Cookes Peak, Luna County, New Mexico, USA. All virgilluethite crystals are pseudomorphs after sidwillite and occur as aggregates of sub-parallel platy crystals. Associated minerals include sidwillite, raydemarkite, tianhuixinite, ilsemannite, jordisite, powellite, fluorite, baryte, pyrite, and quartz. Virgilluethite is pale yellow-green in transmitted light, transparent with white streak and vitreous luster. It is flexible with a Mohs hardness of ∼2; cleavage is perfect on {010}. No twinning was observed visually. The measured and calculated densities are 3.71(5) and 3.69 g/cm3, respectively. Virgilluethite is insoluble in water or hydrochloric acid. An electron probe microanalysis yielded an empirical formula (Mo1.00)O3·H2O based on 4 O apfu. Virgilluethite is the natural analogue of the β-form of MoO3·H2O, which was first synthesized over a century ago (Rosenheim & Davidsohn 1903). It is monoclinic, space group P21/c, with unit-cell parameters a = 7.2834(3), b = 10.6949(6), c = 7.4861(3) Å, β = 112.779(2)°, V = 583.03(5) Å3, and Z = 4. The crystal structure of virgilluethite, which is topologically identical to that of tungstite (WO3·H2O), is characterized by highly distorted and elongated MoO5(H2O) octahedra that share four corners in the equatorial plane with one another to form sheets parallel to (010). These sheets, analogous to those in sidwillite, are held together by H-bonding between the H2O molecule and the O atom in the axial position in the adjacent sheets. Virgilluethite and raydemarkite are dimorphs of MoO3·H2O. Unlike virgilluethite, the MoO6 octahedra in raydemarkite share edges to form isolated double chains, resembling those found in zhenruite, (MoO3)2·H2O.

Two new mineral species, taniajacoite and strontioruizite, ideally SrCaMn3+2Si4O11(OH)4·2H2O and Sr2Mn3+2Si4O11(OH)4·2H2O, respectively, have been identified from the N'Chwaning III mine, Kalahari manganese field, South Africa. Both minerals occur as brown radiating groups or aggregates of acicular or prismatic crystals, with individual crystals up to 0.15 × 0.04 × 0.02 mm for taniajacoite and 1.3 × 0.2 × 0.2 mm for strontioruizite. Minerals associated with taniajacoite include sugilite, aegirine, pectolite, richterite, potassic-ferri-leakeite, and lipuite, whereas those associated with strontioruizite include sugilite, potassic-magnesio-arfvedsonite, and lipuite. Both taniajacoite and strontioruizite are brown in transmitted light, transparent with very light brown streak and vitreous luster. They are brittle and have a Mohs hardness of 5–5.5; cleavage is good on {010} and no parting or twinning is observed macroscopically. The measured and calculated densities are 3.05(2) and 3.09 g/cm3, respectively, for taniajacoite and 3.20(2) and 3.16 g/cm3 for strontioruizite. Optically, both taniajacoite and strontioruizite are biaxial (–), with α = 1.686(2), β = 1.729(2), γ = 1.746(2) (white light), 2V (meas.) = 63.7(5)°, 2V (calc.) = 62.5° for the former and α = 1.692(2), β = 1.734(2), γ = 1.747(2) (white light), 2V (meas.) = 59.1(5)°, 2V (calc.) = 56.6° for the latter. The calculated compatibility index based on the empirical formula is 0.008 for taniajacoite and 0.015 for strontioruizite. An electron microprobe analysis yielded an empirical formula (based on 17 O apfu) of Sr(Ca0.81Sr0.19)Σ1.00(Mn3+1.90Fe3+0.15Al0.01)Σ2.06Si3.96O11(OH)4·2H2O for taniajacoite and (Sr1.61Ca0.42)Σ2.03(Mn3+1.95Fe3+0.05)Σ2.00Si3.98O11(OH)4·2H2O for strontioruizite. Taniajacoite and strontioruizite are isostructural with ruizite. Strontioruizite, like ruizite, is monoclinic with space group C2 and unit-cell parameters a = 9.1575(4), b = 6.2857(4), c = 12.0431(6) Å, β = 91.744(4)°, and V = 692.90(6) Å3, whereas taniajacoite is triclinic, with space group C1 and a = 9.1386(5), b = 6.2566(3), c = 12.0043(6) Å, α = 90.019(4), β = 91.643(4), γ = 89.900(4)°, and V = 686.08(6) Å3. Their structures are characterized by chains of edge-sharing MnO6 octahedra extended along [010], which are linked together by corner-shared SiO4 tetrahedra in four-membered [Si4O11(OH)2] linear clusters, giving rise to a so-called “hetero-polyhedral framework”. The large cations Sr2+ and Ca2+ occupy the seven-coordinated interstices. Unlike monoclinic ruizite and strontioruizite, taniajacoite with Sr:Ca ≈ 1:1 is triclinic, owing to the ordering of Sr2+ and Ca2+ into two crystallographically distinct sites, indicating an incomplete solid solution between Ca and Sr endmembers. The unit-cell volumes for ruizite, taniajacoite, and strontioruizite appear to vary linearly with the Sr/(Ca + Sr) ratio.

A new mineral species, murphyite (IMA 2021-107), ideally Pb(TeO4), has been found from the Grand Central mine, Tombstone, Arizona, USA. It occurs as bladed or prismatic crystals on top of a quartz matrix. Associated minerals include chlorargyrite, emmonsite, ottoite, stolzite, scheelite, schieffelinite, quartz, and jarosite. Individual crystals of murphyite are up to 0.20 × 0.05 × 0.05 mm in size. Twinning is common on {100}. Murphyite is colorless to very pale yellow in transmitted light, transparent with white streak and adamantine luster. It is brittle and has a Mohs hardness of ∼3½, with perfect cleavage on {100}. The calculated density is 7.579 g/cm3. Murphyite is insoluble in water or hydrochloric acid. An electron microprobe analysis yielded the empirical formula (based on 4 O apfu): (Pb0.96Fe0.03Mn0.02)Σ1.01[(Te0.61W0.38)Σ0.99O4], which can be simplified to Pb[(Te,W)O4]. Murphyite is the Te-analogue of raspite, Pb(WO4), and represents the first mineral with Te6+ substituting for W6+ over 50%. It is monoclinic with space group P21/a and unit-cell parameters a = 13.6089(3), b = 5.01750(10), c = 5.5767(2) Å, β = 107.9280(10)°, V = 362.302(17) Å3, and Z = 4. Its crystal structure consists of distorted MO6 (M = Te + W) octahedra sharing edges to form zigzag chains running parallel to [010]. These chains are linked together by PbO7 polyhedra. Compared to raspite, the substitution of W6+ by Te6+, which has a smaller ionic radius, results in a noticeable structural change: a significant decrease in MO6 octahedral angle distortion, with a concomitant increase in both MO6 octahedral volume and average Pb–O bond length. The unit-cell volume increases from 358.72(4) Å3 for raspite to 362.302(17) Å3 for murphyite. Raman spectroscopic data show that the major peak ascribable to M–O symmetrical stretching vibrations within the MO6 octahedron is centered at 870 cm−1 for raspite but at 881 cm−1 for murphyite.

A new mineral species, raygrantite, ideally Pb 10 Zn(SO 4 ) 6 (SiO 4 ) 2 (OH) 2 , has been found in the Big Horn Mountains, Maricopa County, Arizona, USA. Associated minerals are galena, anglesite, cerussite, lanarkite, leadhillite, mattheddleite, alamosite, hydrocerussite, caledonite, and diaboleite. Raygrantite crystals are bladed with striations parallel to the elongated direction (the c axis). Twinning (fish-tail type) is pervasive on (1 2 ). The mineral is colorless, transparent with white streak, and has a vitreous luster. It is brittle and has a Mohs hardness of ∼3; cleavage is good on {120} and no parting was observed. The calculated density is 6.374 g/cm 3 . Optically, raygrantite is biaxial (+), with n α = 1.915(7), n β = 1.981(7), n γ = 2.068(9), 2V meas = 76(2)°, and 2V calc = 85°. It is insoluble in water, acetone, or hydrochloric acid. An electron microprobe analysis yielded the empirical formula Pb 2+ 9.81 Zn 2+ 0.93 (S 1.00 O 4 ) 6 (Si 1.05 O 4 ) 2 (OH) 2 . Raygrantite is a new member of the iranite mineral group. It is triclinic, with space group P and unit-cell parameters a 9.3175(4), b 11.1973(5), c 10.8318(5) A, α 120.374(2), β 90.511(2), γ 56.471(2)°, and V 753.13(6) A 3 . Its crystal structure, refined to R 1 = 0.031, is characterized by slabs that lie parallel to (120) of SO 4 and SiO 4 tetrahedra with ZnO 4 (OH) 2 octahedra, held together by Pb 2+ cations displaying a wide range of Pb–O bond distances. The discovery of raygrantite indicates that, in addition to complete OH–F and Cu–Zn substitutions, there is also a complete substitution between (CrO 4 ) 2– and (SO 4 ) 2– in the iranite group of minerals, pointing to the possible existence of a number of other (SO 4 ) 2– -bearing iranite-type phases yet to be found or synthesized.

Dicobalt (II) hydroxo-selenite: Hydrothermal synthesis, crystal structure and magnetic properties of Co2SeO3(OH)2

A new mineral, petersite-(Ce), ideally Cu 2+ 6 Ce(PO 4 ) 3 (OH) 6 ·3H 2 O (IMA2014-002), has been found in the Cherry Creek District of Yavapai County, Arizona, USA. It is a secondary alteration mineral associated with malachite, chlorite, a biotite phase, quartz, albite, orthoclase, hematite, chalcopyrite, and an uncharacterized hisingerite-like mineral. Petersite-(Ce) occurs as sprays of yellowish-green, acicular crystals approximately 20 × 20 × 50 μm in size. It has a white streak with vitreous luster. The mineral is brittle and has a Mohs hardness of ∼3.5; no cleavage or parting was observed. The calculated density is 3.424 g/cm 3 . An electron microprobe analysis resulted in an empirical chemical formula of Cu 6.05 (Ce 0.18 Y 0.16 La 0.12 Nd 0.09 Gd 0.03 Pr 0.02 Dy 0.01 Sm 0.01 Ca 0.42 ) Σ1.04 [(PO 4 ) 2.54 (SiO 4 ) 0.14 (PO 3 OH) 0.32 (OH) 6 ]·3.65H 2 O. Petersite-(Ce) is hexagonal, with space group P 6 3 / m and unit-cell parameters a 13.2197(18) A, c 5.8591(9) A, and V 886.8(4) A 3 , Z = 2. It is the Ce analogue of petersite-(Y) and exhibits the mixite structure type. The mixite group can be expressed by the general formula Cu 2+ 6 A ( T O 4 ) 3 (OH) 6 · 3H 2 O, where nine-coordinated A is a rare earth element, Al, Ca, Pb, or Bi, and T is P or As. The structure of petersite-(Ce) is characterized by chains of edge-sharing CuO 5 square-pyramids along c . These chains are connected in the a-b plane by edge-sharing CeO 9 polyhedra and corner-sharing PO 4 tetrahedra. Hydroxyl groups occupy each corner of the CuO 5 polyhedra not shared by a neighboring P or Ce atom. Each CeO 9 polyhedron is surrounded by three zeolitic channels. The walls of the channels, parallel to c , are six-membered, hexagonal rings composed of CuO 5 and PO 4 polyhedra in a ratio of 2:1, respectively, and contain H 2 O molecules. In our model of petersite-(Ce), we defined one distinct H 2 O site positioned to form a ring inside the channel, although there are many statistically possible locations.

Vanadiocarpholite, Mn2+V3+Al(Si2O6)(OH)4, occurs at the Molinello mine (Liguria, Italy) in mm-thick veins and in open fissures in a silicified wood sample from Mn-ore bearing cherts. Vanadiocarpholite is found as millimetric aggregates of acicular crystals associated with coatings and crystals of dark-green volborthite and quartz; rarely strongly elongated (001) pris- matic crystals up to 400 µm are also found. The crystals vary in colour from honey yellow-brown and brown (prismatic crystals) to pale straw-yellow (acicular crystal aggregates); they are brittle (prismatic crystals) to flexible (acicular crystals), transparent and non-fluorescent, with vitreous to silky lustre (prismatic crystals and acicular crystal aggregates, respectively) and nearly white streak; they show a perfect {010} cleavage; parting and twinning were not observed. The empirical formula of vanadiocarpholite, derived from microprobe analyses and structural refinement, approaches the ideal formula, Mn2+V3+Al(Si2O6)(OH)4; however, a wide compositional range is detected, mainly due to a solid solution with carpholite (V3+ vs Al substitution). X-ray single crystal data give the refined cell parameters a = 13.830(2) A, b = 20.681(3) A, c = 5.188(1) A and V = 1483.86 A3 in the space group Ccca. Micrometric crystals of vanadiocarpholite were also investigated by transmission and analytical electron microscopy. TEM analyses show a good agreement with WDS and XRD data, but disordered layer stacking sequences are observed. The crystal structure refinement indicates vanadiocarpholite to be isotypic with carpholite, therefore it belongs to the carpholite group together with carpholite, magnesiocarpholite, ferrocarpholite, balipholite and potassic-carpholite.

Kodamaite, ideally Na3(Ca5Na)6Si16O36(OH)4F2·14−xH2O, where x = ∼5, is a new mineral discovered at the Poudrette quarry, Mont Saint-Hilaire, Quebec, Canada. It develops in spherulitic aggregates up to ∼2 mm across, comprising thin, platy to bladed crystals, with individual crystals averaging <0.05 × 0.5 mm. Crystals are dominated by the form pinacoid {100} with a lesser {hk0} form and typically range from tan to creamy-yellow to white in color, less often being colorless, light or dark green, or white. Associated minerals include eudialyte-group minerals, aegirine, a clinoamphibole, serandite-group minerals, natrolite, molybdenite, pyrite, fluorite, sodalite, catapleiite, rinkite-group minerals, albite, villiaumite, pyrochlore, fluorapatite, microcline, and erdite. Kodamaite is translucent to transparent and has a silky to slightly vitreous luster, a white streak, a Mohs hardness of ∼2, a perfect {001} cleavage, a sectile tenacity, and a smooth fracture. The mineral shows a pronounced bluish-white fluorescence under both long- and medium-wave ultraviolet radiation, much less so under short-wave radiation. The calculated density is 2.16 g/cm3. Optically, kodamaite is presumed to be optically biaxial, but its optical properties could not be readily discerned. An average nD = 1.507 (for λ = 590 nm) was calculated using data from the refined crystal structure. It is non-pleochroic, has low birefringence (first-order gray) and crystals are length slow and show no dispersion. The Raman spectrum shows two strong peaks at 607 (O–Si–O stretch) and 1070 cm−1 (Si–O stretch), along with several weaker ones over the range of ∼100–500 cm−1 arising from a combination of alkali–O bonds and lattice vibrations. An average of 11 energy-dispersive spectroscopic analyses gave Na2O 8.55, CaO 16.80, Fe2O3 0.39, SiO2 60.76, F 2.57, Cl 0.11, H2O (calc.) 12.49, O=F −1.08, O=Cl −0.02, total 100.98 wt.%. The empirical formula [based on Σ16(Si+S6+) cations apfu] is Na3.14(Ca4.72Na1.30Fe0.08)Σ6.00(Si15.92S6+0.08)Σ16O36.09(OH3.82F0.13Cl0.08)Σ4.00F2·9H2O. The crystal-structure formula is NaNa2Ca2Ca2(NaCa)2Si16O36(OH)4F2·14−xH2O with x = ∼5, which may be simplified to Na3(Ca5Na)6Si16O36(OH)4F2·9H2O. The mineral is triclinic, crystallizing in space group P, with a = 9.609(2), b = 9.630(2), c = 15.739(3) Å, α = 75.21(3), β = 85.22(3), γ = 60.12(3) °, V = 1219.3(1) Å3, Z = 1. The strongest six lines of the X-ray powder-diffraction pattern [dobs in Å (Iobs) (hkl)] are: 15.197 (100) (001), 3.833 (7) (004), 3.068 (7) (005), 2.996 (18) , 2.780 (14) , 1.831 (9) . The crystal structure was refined to R = 8.43%, wR2 = 23.50% using single-crystal X-ray diffraction data (1578 reflections with Fo > 4σFo). Kodamaite has a strongly layered crystal structure, with a motif based on single sheets of SiO4 tetrahedra (T) that are composed of regular, planar, six-membered rings (with a u6 arrangement; apices of the tetrahedra all point in a common direction, up = u). The regular rings of tetrahedra are linked in the (001) plane by SiO3(OH) tetrahedra, whose apical directions are opposite to those in the ring (down; d). Linkages between the two types of tetrahedra give rise to an irregular, six-membered ring of tetrahedra with a u2du2d arrangement. The combination of regular and irregular six-membered rings of tetrahedra produces a three-connected (63)4 net. Two symmetry-related T layers, designated T2 and −T2, sandwich a closest-packed layer of edge-sharing Naφ6 and Caφ6 octahedra and Naφ8 polyhedra (φ = undefined ligand; O, F), forming a quasi-layer of octahedra (O). Refinement of the crystal structure shows the Ca sites are dominated by Ca with small amounts of Na (9:1 ratio); one of the sites has an equal concentration of Ca and Na, suggesting ordering of the two in a single site. The arrangement of T and O layers produces a TOT module with the interlayer space being occupied by H2O groups. Charge-balance arguments and observed anion–anion distances support ordering of F in a single, distinct site. The complete crystal structure of kodamaite conforms to a scheme, which is similar to that of the closely related minerals martinite and ellingsenite. All are classed in the gyrolite supergroup, which includes minerals in five groups, all having similar but distinct crystal-structure features. The crystal-chemical relationships among the groups and implications in terms of the stacking of various modules are presented and discussed. Kodamaite is a late-stage mineral that developed under hydrothermal conditions at T < 200 °C, most likely under high to very high alkalinity. The interaction of these fluids with pre-existing minerals, including pectolite, eudialyte-group minerals, and sodalite, is likely essential to the formation of the kodamaite.

A new chain-silicate mineral species, yangite, ideally PbMnSi 3 O 8 ·H 2 O, has been found on a specimen from the Kombat mine, Otavi Valley, Namibia. Associated minerals are melanotekite and rhodochrosite. Yangite is colorless to pale brown in transmitted light, transparent with white streak and vitreous luster. Broken pieces of yangite crystals are bladed or platy, and elongated along [010]. It is sectile with a Mohs hardness of ~5; cleavage is perfect on {101} and no twinning or parting was observed. The measured and calculated densities are 4.14(3) and 4.16 g/cm 3 , respectively. Optically, yangite is biaxial (−), with n α = 1.690(1), n β = 1.699(1), n γ = 1.705(1), Y = b, Z ^ c = 11°, and 2 V meas = 77(2)°. It is insoluble in water, acetone, and hydrochloric acid. An electron microprobe analysis demonstrated that the sample was relatively pure, yielding the empirical formula (with calculated H 2 O) Pb 1 . 00 Mn 1 . 00 2 + Si 3 . 00 O 8 ⋅ H 2 O . Yangite is triclinic and exhibits space group symmetry P 1 ¯ with unit-cell parameters a = 9.6015(9), b = 7.2712(7), c = 7.9833(8) A, α = 105.910(4), β = 118.229(4), γ = 109.935(5)°, and V = 392.69(7) A 3 . Its crystal structure is based on a skeleton of double wollastonite SiO 4 tetrahedral chains oriented parallel to [010] and interlinked with ribbons of Mn- and Pb-polyhedra. Yangite represents the first chain silicate with two-connected double chains and possesses all of the structural features of a hypothetical triclinic Ca 2 Si 3 O 8 ·2H 2 O phase proposed by Merlino and Bonaccorsi (2008) as a derivative of the okenite structure. The difference in the H 2 O component between the hypothetical phase and yangite likely is a consequence of the larger Pb 2+ with its lone-pair electrons in yangite replacing the smaller Ca 2+ in the hypothetical phase.

A new mineral species, petermegawite, ideally Al6(Se4+O3)3[SiO3(OH)](OH)9⋅10H2O, was discovered at the El Dragón mine, Potosí Department, Bolivia. It occurs as aggregates of bladed or tabular crystals. Associated minerals are Co-bearing krut′aite–penroseite (matrix), chalcomenite, ‘clinochalcomenite’ (not IMA approved), molybdomenite, lepidocrocite, goethite, ahlfeldite, and calcite. Petermegawite is colorless in transmitted light and transparent with a white streak and vitreous luster. It is brittle and has a Mohs hardness of 2–2½. Cleavage is perfect on {001}. The measured and calculated densities are 2.27(5) and 2.32 g/cm3, respectively. Optically, petermegawite is biaxial (+), with α = 1.545(5), β = 1.554(5), γ = 1.567(5) (white light). An electron microprobe analysis yielded an empirical formula (based on 10 non-H cations pfu) of Al6.00[(Se0.89S0.11)Σ1.00O3]3[(Si0.90Al0.07)Σ0.97O2.81(OH)1.19](OH)9⋅10H2O, which can be simplified to Al6[(Se,S)O3]3[(Si,Al)O3(OH)](OH)9⋅10H2O. Petermegawite is orthorhombic, space group Cmc21 with unit-cell parameters a = 16.2392(2), b = 10.96370(10), c = 15.3367(2) Å, V = 2730.57(5) Å3, and Z = 4. Its crystal structure is characterized by clusters of six-membered rings of edge-sharing AlO6 octahedra with an SiO3(OH) tetrahedron situated at the center of each ring and three Se4+O3 triangular pyramids appended outside the ring. These clusters are joined together by hydrogen bonds to form heteropolyhedral layers parallel to (001). The H2O molecules that are not bonded to any non-H cations are sandwiched between the layers. The cluster formed by a six-membered AlO6 octahedral ring with an SiO3OH tetrahedron at the center of the ring in petermegawite has the composition [Al6(SiO3OH)O6(OH)9(H2O)6]6−. It is topologically identical to the clusters of composition [Al6(AsO4)O7(OH)9(H2O)5]8− that are found in bettertonite and penberthycroftite. As a new polyoxometalate building block, this type of cluster may be expressed with a general chemical formula [TM6X25], where T = tetrahedrally coordinated cation, M = octahedrally coordinated cation, and X = O, OH, H2O.

Crystal structure of a new high-pressure phase, K 0.82Mg 1.68(Cr 2.84Fe 0.84Ti 2.11Zr 0.08)O 12, with one-dimensional tunnels

A new organic mineral species, lianbinite, ideally (NH4)(C2H3O3)(C2H4O3), was discovered from the western end of Pusch Ridge in the Santa Catalina Mountains, north of Tucson, Arizona, U.S.A. It occurs as bladed or acicular crystals, associated with baryte, fluorite, glecklerite, jarosite, jimkrieghite, quartz, and rasmussenite. Lianbinite is colorless, transparent with a white streak and vitreous luster. It is brittle and has a Mohs hardness of 1–1½; cleavage is perfect on {100}. No parting or twinning was observed. The calculated density is 1.497 g/cm3. The chemical composition of lianbinite was determined with a Thermo Finnigan DELTAplus XL Elemental Combustion System equipped with a mass spectrometer, yielding an empirical formula (N0.98H4.06)(C1.98H3O3)(C1.99H3O3), or N0.98C3.97H11.06O6, on the basis of 6 O apfu. Lianbinite is the natural counterpart of synthetic (NH4)(C2H3O3)(C2H4O3), which is isostructural with synthetic K(C2H3O3)(C2H4O3) and Rb(C2H3O3)(C2H4O3). It is monoclinic with space group P21/c, and unit-cell parameters a = 3.91305(11), b = 18.7499(4), c = 10.7214(2) Å, β = 107.444(2)°, V = 750.45(3) Å3, and Z = 4. The crystal structure of lianbinite contains two forms of glycolate units: glycolate anions (GAs) and glycolic acid molecules (GMs). These two units are linked together by hydrogen bonds to form a three-dimensional network with two kinds of channels extending along [100]. The large channel is surrounded by O atoms, with (NH4)+ groups situated inside, whereas the small one is enclosed by H atoms. The discovery of lianbinite, together with eight other glycolate minerals documented thus far, implies that glycolate minerals may be rather widespread in nature, thus serving as a potential reservoir for biologically fixed carbon.

Two new organic minerals, alterite and magnesioalterite, ideally Zn2Fe3+4(SO4)4(C2O4)2(OH)4·17H2O and Mg2Fe3+4(SO4)4(C2O4)2(OH)4·17H2O, respectively, were discovered in carbonaceous petrified wood from an unnamed uranium prospect, the Vermillion Cliffs, Coconino County, Arizona, USA. Associated minerals include gypsum, alunogen, natrojarosite, sulfur, celestine, and quartz. Both alterite and magnesioalterite are yellowish green in transmitted light and transparent with white streak and vitreous luster. They are brittle and have a Mohs hardness of ∼1.5; cleavage is perfect on (001). No parting or twinning was observed. The measured densities are 2.18(4) and 2.17(3) g/cm3 for alterite and magnesioalterite, respectively. Optically, alterite is biaxial (+), with α = 1.545(5), β = 1.565(5), γ = 1.635(5), 2Vmeas. = 56(2)°, 2Vcal. = 58°. Magnesioalterite is also biaxial (+), with α =1.520 (5), β = 1.578 (6), γ = 1.610 (5), 2Vmeas. = 74(2)°, 2Vcal. = 76.5°. Both new minerals are insoluble in water, but slowly dissolve in hydrochloric acid. An electron microprobe analysis, together with data from an Elemental Combustion System for C, yielded the empirical formula (based on 45 O apfu) (Zn0.84Fe2+0.57Mg0.48Mn0.14)Σ2.03Fe3+4.00(S0.99O4)4(C2O4)2(OH)4·17H2O for alterite and (Mg0.74Zn0.60Fe2+0.58Mn0.09)Σ2.01Fe3+4.00(SO4)4.00(C2O4)2(OH)4·17H2O for magnesioalterite, both of which can be simplified to (Zn,Fe,Mg,Mn)2Fe3+4(SO4)4(C2O4)2(OH)4·17H2O and (Mg,Zn,Fe2+,Mn)2Fe3+4(SO4)4(C2O4)2(OH)4·17H2O, respectively. The measured δ13C ‰ value for the carbonaceous petrified wood on which the minerals were found is −23.1 and for alterite and magnesioalterite is 0.2. Alterite and magnesioalterite constitute a complete solid solution. They are monoclinic with the same space group, C2/c. The unit-cell parameters are a = 16.7656(15), b = 9.4074(7), c = 25.351(3) Å, β = 108.258(5)°, V = 3797.1(6) Å3 for alterite and a = 16.7696(5), b = 9.4020(2), c = 25.3466(8) Å, β = 108.2520(10)°, V = 3795.28(18) Å3 for magnesioalterite. The crystal structures of alterite and magnesioalterite are characterized by four-membered clusters of corner-sharing Fe3+(O5OH) octahedra. These clusters are linked by SO4 tetrahedra along the b axis and by the oxalate groups (C2O4)2− along the a axis to form sheets parallel to (001). Between the sheets are layers of M2+(H2O)6 octahedra (M = Zn2+, Mg2+, Fe2+, and Mn2+) and three symmetrically distinct H2O molecules that are not bonded to any non-H cations. The linkage between the sheets and the layers is achieved by hydrogen bonds, accounting for the good cleavage parallel to (001). Alterite and magnesioalterite are two of five double-salt minerals with hydrated sulfate-oxalates, after coskrenite-(Ce), Ce2(SO4)2(C2O4)·8H2O; levinsonite-(Y), YAl(SO4)2(C2O4)·12H2O; and zugshunstite-(Ce), CeAl(SO4)2(C2O4)·12H2O. They are also the most hydrated among the 34 oxalate minerals reported thus far. Noticeably, both alterite and magnesioalterite contain a significant amount of Fe2+ substituting for Mg and Zn, pointing to the likelihood for the existence of a Fe2+-analogue of alterite.

A new mineral species, hydroxymcglassonite-(K), ideally KSr4Si8O20(OH)·8H2O, has been found in the Wessels mine, Kalahari Manganese Field, Northern Cape Province, South Africa. It is granular (<0.05 mm), associated with meieranite, sugilite, aegirine, pectolite, and yuzuxiangite. The mineral is colorless, transparent with a white streak and a vitreous luster. It is brittle and has a Mohs hardness of 4.5–5.0; cleavage is perfect on {001} and no parting or twinning was observed. The measured and calculated densities are 2.60(3) and 2.614 g/cm3, respectively. Optically, hydroxymcglassonite-(K) is uniaxial (+), with ω = 1.555(5), ε = 1.567(5) (white light), and absorption O > E. Hydroxymcglassonite-(K) is insoluble in water or hydrochloric acid. An electron microprobe analysis yielded an empirical formula (based on 13 non-H cations pfu) K1.01(Sr2.99Ca1.03)Σ4.02Si7.99O20(OH)·8H2O, which can be simplified to K(Sr,Ca)4Si8O20(OH)·8H2O. Hydroxymcglassonite-(K) is tetragonal with space group P4/mnc and unit-cell parameters a = 9.0792(2), c = 16.1551(9) Å, V = 1331.70(9) Å3, and Z = 2. It is isostructural with hydroxyapophyllite-(K), KCa4Si8O20(OH)·8H2O, with Sr substituting for Ca. The crystal structure of hydroxy-mcglassonite-(K) is characterized by SiO4 tetrahedra sharing corners to form (Si8O20)8– sheets parallel to (001), which are connected by the K and B (= Sr + Ca) cations, as well as hydrogen bonding. The K cation is coordinated by eight H2O groups, and the average K–O distance of 2.941(3) Å is shorter than that of 2.950(3)–2.975(3) Å in hydroxyapophyllite-(K) or fluorapophyllite-(K). The B cation is sevenfold-coordinated (4O + 2H2O + OH), and the average B-O distance of 2.522(3) Å is noticeably longer than that of 2.422–2.435 Å in hydroxyapophyllite-(K) or fluorapophyllite-(K). The Raman spectra of hydroxymcglassonite-(K) and hydroxyapophyllite-(K) are very comparable, especially in the O-H stretching region. The discovery of hydroxymcglassonite-(K), the first Sr-bearing mineral of the apophyllite group, implies that more Sr-bearing members of the group may be found in nature or synthesized in laboratories, but the possibility for an incomplete solid solution between hydroxyapophyllite-(K) and hydroxymcglassonite-(K), due to the size difference between Sr2+ and Ca2+, cannot be ruled out.