Orange Brown Research Articles

Argentotetrahedrite-(Cd), Ag6(Cu4Cd2)Sb4S13, a new member of the tetrahedrite group from Rudno nad Hronom, Slovakia.

AbstractArgentotetrahedrite-(Cd), Ag6(Cu4Cd2)Sb4S13, has been approved as a new mineral species by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association using samples from Rudno nad Hronom, Slovak Republic. It occurs as anhedral grains up to 30 μm in size, steel-grey to black in colour, with a metallic lustre, in association with greenockite and other tetrahedrite-group minerals [argentotetrahedrite-(Zn) and tetrahedrite-(Zn)], earlier base-metal minerals, Ag sulfides and sulfosalts (acanthite, pyrargyrite and polybasite) and later galena. Argentotetrahedrite-(Cd) is isotropic, grey in colour, with a creamy tint and rapidly (tens of minutes) tarnishes to orange–brown. Reflectance data for Commission on Ore Mineralogy (COM) wavelengths in air are [λ (nm), R (%)]: 470, 30.4; 546, 30.3; 589, 30.3; and 650, 28.7. The chemical formula of the samples studied, recalculated on the basis of ΣMe = 16 atoms per formula unit, is: (Ag3.28Cu2.72)Ʃ6.00[Cu4(Cd1.68Fe0.27Zn0.16)]Ʃ6.11(Sb3.71As0.15)Ʃ3.86S12.79. Argentotetrahedrite-(Cd) is cubic, I$\bar{4}$3m, with a = 10.65(2) Å, V = 1208(4) Å3 and Z = 2. Argentotetrahedrite-(Cd) is isotypic with other members of the tetrahedrite group. The structural relationship between argentotetrahedrite-(Cd) and other members of the freibergite series are discussed and previous findings of this species are briefly reviewed.

SEEDS, PODS AND PETIOLE GLAND’S CHARACTERISTICS OF LEUCAENA SPP. ANALYTICAL STUDY (A)

Twenty-two species were extracted from the Leucaena Spp. Data were collected on their characteristics, which differed from each other and were classified accordingly. Statistical analysis revealed that there were many differences between species in some traits; each type is itself in other qualities. Therefore, we presented the qualities that need to be described in order to identify differences. The study included the qualities related to seeds, pods and petiole gland. The seeds were aligned in Pods in three forms, while the shape of the seed came in two types. Only two types of species differed in the status of the opening of the pod (dehiscence). As for the thickness of the wall of the Pods, the species varied greatly, and the highest was the Papery. The rate of openness of the Pods was very high at 90.9% for one margin. The partitioning between seeds within Pods did not register more than two types, and it tended to have no partition by 72.7%. Only two shapes were distinguished in terms of the clarity of the seed chamber on the surface of the pods and 16 times the uncertainty was repeated ( not partitioned ) , leaving 6 replicates of the possible type of clarity ( partitioned ) . The colors of Pods differed very much, and each type had its own color except for some exceptions. The most frequent color was (To Orange Brown) with five replicates and the color (Mid Orange Brown) four times and the remaining types remained independent of colors. There was a high correlation between seed and pods traits and in some cases reached 90% at the probability of 1%. The length of the seed ranged between 4.9 mm - 10.6 mm but distributed over all types of tree under study. Each seed type had a specific seed length. The correlation coefficient between seed width and seed length was high at a probability of 1% to 0.775. Seeds / Kg was varied even within one species and was between 8700 - 70000 seeds / kg. There were only two forms that showed the accompaniment of the gland on the throat while three forms of the gland type were recorded but the gland height had a variety of forms.

Wilhelmgümbelite, [ZnFe2+Fe33+(PO4)3(OH)4(H2O)5]·2H2O, a new schoonerite-related mineral from the Hagendorf Süd pegmatite, Bavaria

AbstractWilhelmgümbelite, ideally [ZnFe2+Fe33+(PO4)3(OH)4(H2O)5]·2H2O, is a new secondary phosphate mineral related closely to schoonerite, [ZnMnFe22+Fe3+(PO4)3(OH)2(H2O)7]·2H2O, from oxidized zones of the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Wilhelmgümbelite occurs as radiating sprays of needle-like rectangular laths, up to 0.2 mm long and with colour varying from light yellow brown to orange red. Cleavage is perfect parallel to {010}. The mineral is associated closely with an oxidized pseudomorph of phosphophyllite, recently named steinmetzite. Other associated minerals are albite, apatite, chalcophanite, jahnsite, mitridatite, muscovite and quartz. The calculated density of wilhelmgümbelite is 2.82 g cm–3. It is optically biaxial (+) with α = 1.560(2), β = 1.669(2), γ = 1.718(2), 2V(meas) = 63(1)° and 2V(calc.) = 65°. Dispersion is weak with r > v, orientation X = b, Y = c, Z = a. Pleochroism is weak, with coloursZ = orange brown, Y = yellow brown, X = light yellow brown, Z >> Y > X. Electron microprobe analyses (average of seven analyses, seven crystals) with H2O and FeO/Fe2O3 calculated on structural grounds, gave FeO 5.8, Fe2O3 25.0, MnO 2.6, ZnO 16.4, P2O5 28.7, H2O 23.4, total 101.9 wt.%. The empirical formula, scaled to 3 P and OH– adjusted for charge balance is Zn1.50Mn0.272+Fe0.602+Fe2.333+(PO4)3·(OH)2.73(H2O)8.27. The structural formula is [Zn(Mn0.27Fe0.733+)∑1.0(Zn0.25Fe0.152+Fe0.603+)∑1.0(Zn0.25Fe0.452+)∑0.7Fe3+(PO4)3(OH,H2O)9]·2H2O.Wilhelmgümbelite has orthorhombic symmetry, Pmab, Z = 4, with the unit-cell parameters of a = 10.987(7) Å, b = 25.378(13) Å, c = 6.387(6) Å and V = 1781(2) Å3. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(Iobs) (hkl)] 12.65 (100) (020); 8.339 (5) (120); 6.421 (14) (001); 6.228 (8) (011); 4.223 (30) (120) and 2.111 (7) (0 12 0). Wilhelmgümbelite is an oxidized form of schoonerite, with the Mn2+ replaced principally by Fe3+. Its structure differs from that of schoonerite in having the Zn partitioned between two different sites, one five-coordinated as in schoonerite and the other tetrahedrally coordinated. Wilhelmgümbelite also differs structurally from schoonerite in having partial occupation of one of the Fe sites, which appears to be correlated with the Zn partitioning.

Flurlite, Zn3Mn2+Fe3+(PO4)3(OH)2·9H2O, a new mineral from the Hagendorf Süd pegmatite, Bavaria, with a schoonerite-related structure

AbstractFlurlite, ideally Zn3Mn2+Fe3+(PO4)3(OH)2·9H2O, is a new mineral from the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Flurlite occurs as ultrathin (<1 μm) translucent platelets that form characteristic twisted accordion-like aggregates. The colour varies from bright orange red to dark maroon red. Cleavage is perfect parallel to (001). The mineral occurs on mitridatite and is closely associated with plimerite. Other associated minerals are beraunite, schoonerite, parascholzite, robertsite and altered phosphophyllite. The calculated density of flurlite is 2.84 g cm–3. It is optically biaxial (–), α = 1.60(1), β= 1.65(1) and γ = 1.68(1), with weak dispersion and parallel extinction, X ≈ c, Y ≈ a, Z ≈ b. Pleochroism is weak, with colours: X = pale yellow, Y = pale orange, Z = orange brown. Electron microprobe analyses (average of seven) with FeO and Fe2O3 apportioned and H2O calculated on structural grounds, gave ZnO 25.4, MnO 5.28, MgO 0.52, FeO 7.40, Fe2O3 10.3, P2O5 27.2, H2O 23.1, total 99.2 wt.%. The empirical formula, based on 3 P a.p.f.u. is Zn2.5Mn2+0.6Fe2+0.8Mg0.1Fe3+(PO4)3(OH)2·9H2O. Flurlite is monoclinic, P21/m, with the unit-cell parameters (at 100 K) of a = 6.3710(13), b = 11.020(2), c = 13.016(3) Å, β = 99.34 (3)°. The strongest lines in the X-ray powder diffraction pattern are [dobs in Å(I) (hkl)] 12.900(100)(001); 8.375(10)(011); 6.072(14)(101); 5.567(8)(012); 4.297(21)(003); 2.763(35)(040). Flurlite (R1 = 0.057 for 995 F > 4σ(F)) has a heteropolyhedral layer structure, with layers parallel to (001) and with water molecules packing between the layers. The slab-like layers contain two types of polyhedral chains running parallel to [100]: (a) chains of edge-sharing octahedra containing predominantly Zn and (b) chains in which Fe3+-centred octahedra share their apices with dimers comprising Zn-centred trigonal bipyramids sharing an edge with PO4 tetrahedra. The two types of chains are interconnected by corner-sharing along [010]. A second type of PO4 tetrahedron connects the chains to MnO2(H2O)4 octahedra along [010] to complete the structure of the (001) slabs. Flurlite has the same stoichiometry as schoonerite, but with dominant Zn rather than Fe2+ in the edge-shared chains. Schoonerite has a similar heteropolyhedral layer structure with the same layer dimensions 6.4 × 11.1 Å. The different symmetry (orthorhombic, Pmab) for schoonerite reflects a different topology of the layers.

Deposits of the most recent eruption in the Southern Mono Craters, California: Description, interpretation and implications for regional marker tephras

The penultimate eruption in the Mono Craters, Mono County, CA, USA, occurred in the southern section of the volcanic chain, and is herein named the South Mono eruption. The South Mono eruption occurred in 594–648calA.D., and its products consist of widespread Plinian and phreatomagmatic fall, surge and pyroclastic flow deposits. The explosive deposits can be broken into Basal, Orange–Brown (surge dominated) and Upper subunits. The eruptive phase represented by the Upper beds was the most intense and voluminous, dispersing tephra over a wide region of eastern CA and western NV. South Coulee was the only effusive product of the eruption, and comprises the vast majority of the c. 0.4cukm dense-rock equivalent (DRE) volume. The tephra overlies the deposits of Wilson Butte to the south, and is correlated herein with Wood's Tephra 2, and Walker Lake and Turupah Flats regional marker tephra layers. Other dates for these regional tephras may be the result of dating ash redeposited in debris flow events following fire.

Detrital mineral morphology and geochemistry: Methods to characterize and constrain the origin of the Nsanaragati blue sapphires, south-western region of Cameroon

Morphological and geochemical analyses of blue sapphires from the Nsanaragati alluvial gem deposits in the south-western region of Cameroon help to characterize these sapphires, and constrain their source parameters. The gem corundums range in color from pale to dark blue, with rare orange brown. They range from transparent to opaque, with most of the pale blue sapphires being transparent and the dark blue and orange-brown sapphires being opaque. The shape of the sapphires ranges from equant sub-platy to sub-prismatic and are sub-rounded to well-rounded. Very few of these sapphires are round and frosted. The angular lustrous sapphires are associated with a more proximal origin, while, the sub-rounded lustrous grains are either from a distal origin or more reworked. The round frosted grains may include wind worn products from eolian erosion. The LA-ICP-MS geochemical analysis of the sapphires shows minor and trace element enrichments among the identified elements. The main elemental contributions include, Fe (2496–4643ppm), Ti (49–7069ppm), Ca (360–976ppm), Si (485–687ppm) and Ga (149–307ppm) while V (4–41ppm) and Mg (2–42ppm) levels are relatively low, and the remaining element values are less than 9ppm or below their detection limits. Among element ratios, Fe/Mg (96.8–1106.8), Fe/Ti (0.5–81.5), Ti/Mg (14.5–174.1) and Ga/Mg (6.2–89.3) range into high values, while Cr/Ga (<0.01) is very low. The high Fe and Ga and low Mg and Cr values suggest a magmatic origin for these sapphires, possibly xenocrysts from basaltic magmas. They were potentially crystallized from a Ga- and Fe-enriched aluminous alkaline magma.

MANITOBAITE, Na16 Mn2+25 Al8 (PO4)30, A NEW PHOSPHATE MINERAL SPECIES FROM CROSS LAKE, MANITOBA, CANADA

Manitobaite, ideally Na 16 Mn 2+ 25 Al 8 (PO 4 ) 30 , is a new mineral species from Cross Lake, Manitoba, Canada. It occurs as large crystals or cleavage masses intergrown with other phosphate minerals in a phosphate pod in the intermediate and core zones of pegmatite #22 on the southeastern shoreline of a small unnamed island in Cross Lake, Manitoba, about 5 km north–northwest of the Cross Lake settlement, longitude 54° 41′ N, latitude 97° 49′ W. Associated minerals are fluorapatite, chlorapatite, bobfergusonite, eosphorite, dickinsonite, fillowite, triploidite, goyazite, perloffite, beusite, triplite, as well as quartz, K-feldspar, muscovite, schorl, beryl, spessartine, gahnite and (Nb,Ta,Sn) oxides. Manitobaite is opaque in large crystals (up to 4 cm), and transparent to translucent in small ( −3 , respectively. Manitobaite is biaxial negative with α 1.682, β 1.691, γ 1.697 (all ±0.001), with X ∧ a = 31.7° (in β obtuse), Y || b , Z ∧ c = 20.2° (in β acute); 2 V obs = 78.1(6)°, 2 V calc = 77.9°. It is pleochroic X = orange brown, Y = green, Z = greenish brown, with absorption Y ≥ Z > X and dispersion r > v , medium. Manitobaite is monoclinic, Pc , a 13.4516(15), b 12.5153(16), c 26.661(3) A, β 101.579(10)°, V 4397.1(6) A 3 , Z = 2, a:b:c = 1.07482:1:2.13027. The strongest seven lines in the X-ray powder-diffraction pattern [ d in A( I )( hkl )] are: 2.715(100)(242), 2.730(50)(404), 3.494(47)(313), 3.078(27)(317), 2.518(22)( 515), 2.881(21)(119), and 6.260(20)(020). A chemical analysis with an electron microprobe gave P 2 O 5 44.19, Al 2 O 3 6.91, FeO 7.79, MnO 27.57, ZnO 0.54, MgO 0.73, CaO 1.71, Na 2 O 9.97, for a total of 99.58 wt%. The resulting empirical formula, using the valence states of Fe determined by Mossbauer spectroscopy, is Na 15.55 Ca 1.47 Mg 0.88 Fe 2+ 4.19 Mn 2+ 18.78 Zn 0.32 Al 6.54 Fe 3+ 1.05 P 30.08 O 120 based on 120 O 2− anions pfu . The general formula is ( Na ,Ca,□) 16 ( Mn 2+ ,Fe 2+ ,Ca,Al,Fe 3+ ,Mg,Zn) 25 ( Al ,Fe 3+ ,Mg,Mn 2+ , Fe 2+ ) 8 (PO 4 ) 30 , and the end-member formula is Na 16 Mn 2+ 25 Al 8 (PO 4 ) 30 . The crystal structure of manitobaite is an ordered superstructure of the alluaudite arrangement with a cell volume five times that of alluaudite.

Seed Development in Lesquerella fendleri (L.)

The morphological, physiological, and biochemical changes during seed development of Lesquerella fendleri were investigated from 7 days after pollination (DAP) to desiccation. The entire course of seed development lasted ≈49 days and it can be divided into seven sequential stages (I to VII). During the early stages (I to III, 7 to 21 DAP), seed grew rapidly, showing a dramatic increase in size and fresh weight. They contained ≈75% water. During midmaturation stages (IV to V, 28 to 35 DAP), storage lipids, proteins, and other components of dry weights accumulated at maximum rates. The accumulation curves followed a sigmoidal pattern during seed development. As a result of water loss, fresh weight dropped significantly when seed progressed to late-maturation/desiccation stages (VI to VII, 42 to 49 DAP). The size of the seed decreased slightly and the color changed from green to orange–brown. Seed proteins were also analyzed using SDS-PAGE. Proteins with high molecular weights were prominent in developing seed at early stages (I to III). At Stage IV (28 DAP), proteins with low molecular weight appeared, whereas the high-molecular-weight proteins decreased in proportion. These low-molecular-weight proteins became predominant throughout the remaining stages of seed development. Forty-seven percent of freshly harvested seed at 35 DAP were able to germinate after 7 days incubation. The germination percentage increased to a maximum of 95% at 42 DAP after 7 days incubation. The relationships among seed morphology, reserve synthesis, and germination are discussed.

Crown Rot of Strawberry Caused by Macrophomina phaseolina in California.

In 2006 and 2007, severely diseased strawberry (Fragaria × ananassa) plants were observed in five commercial fields in southern California (Orange County). Disease generally occurred in discrete patches. Within such patches, disease incidence ranged from 10 to 75%. Symptoms consisted of wilting of foliage, drying and death of older leaves, plant stunting, and eventual collapse and death of plants. When plant crowns were dissected, internal vascular and cortex tissues were dark brown to orange brown. Fruiting bodies or other fungal structures were not observed. A fungus was consistently isolated from symptomatic crown tissue that had been surface sterilized and placed on acidified corn meal agar (LA-CMA). All isolates produced numerous, dark, irregularly shaped sclerotia that were 67 to 170 μm long and 44 to 133 μm wide. When isolates were grown on 1.5% water agar with dried and sterilized wheat straw, dark, ostiolate pycnidia and hyaline, single-celled, cylindrical conidia were produced. On the basis of these characters, all isolates were identified as Macrophomina phaseolina (1). The symptomatic plants tested negative for Colletotrichum spp., Phytophthora spp., Verticillium dahliae, and other pathogens. Inoculum for pathogenicity tests was produced by growing six isolates on CMA on which sterilized wood toothpicks were placed on the agar surface. After 1 week, toothpicks were removed and inserted 4 to 5 mm deep into the basal crown tissue of potted strawberry plants (cv. Camarosa) grown in soilless, peatmoss-based rooting medium. Ten plants were inoculated per isolate and one toothpick was inserted per plant. Ten control strawberry plants were treated by inserting one sterile toothpick into each crown. All plants were then grown in a shadehouse. After 2 weeks, all inoculated plants began to show wilting and decline of foliage. By 4 weeks, all inoculated plants had collapsed. Internal crown tissue was discolored and similar in appearance to the original field plants. M. phaseolina was isolated from all inoculated plants. Control plants did not exhibit any disease symptoms, and crown tissue was symptomless. The test was repeated and the results were similar. While M. phaseolina has been periodically associated with strawberry in California (3), to my knowledge, this is the first report of charcoal rot disease on commercial strawberry in California. Charcoal rot of strawberry has been reported in Egypt, France, India, Israel, and the United States (Florida and Illinois) (2,4). Similar to previous reports (2,4), many of the affected California fields were not preplant fumigated with methyl bromide + chloropicrin fumigants, and it is possible that under these changing production practices this pathogen may increase in importance in California.

Anion-Selective Interaction and Colorimeter by an Optical Metalloreceptor Based on Ruthenium(II) 2,2‘-Biimidazole: Hydrogen Bonding and Proton Transfer

A new anion sensor [Ru(bpy)2(H2biim)](PF6)2 (1) (bpy = 2,2'-bipyridine and H2biim = 2,2'-biimidazole) has been developed, in which the Ru(II)-bpy moiety acts as a chromophore and the H2biim ligand as an anion receptor via hydrogen bonding. A systematic investigation shows that 1 is an eligible sensor for various anions. It donates protons for hydrogen bonding to Cl-, Br-, I-, NO3-, HSO4-, H2PO4-, and OAc- anions and further actualizes monoproton transfer to the OAc- anion, changing color from yellow to orange brown. The fluoride ion has a high affinity toward the N-H group of the H2biim ligand for proton transfer, rather than hydrogen bonding, because of the formation of the highly stable HF2- anion, resulting in stepwise deprotonation of the two N-H fragments. These processes are signaled by vivid color changes from yellow to orange brown and then to violet because of second-sphere donor-acceptor interactions between Ru(II)-H2biim and the anions. The significant color changes can be distinguished visually. The processes are not only determined by the basicity of anion but also by the strength of hydrogen bonding and the stability of the anion-receptor complexes. The design strategy and remarkable photophysical properties of sensor 1 help to extend the development of anion sensors.

Tillmannsite, (Ag3Hg)(V, As)O4, a new mineral its description and crystal structure

Tillmannsite, (Ag 3 Hg)(V, As)O 4 , was found in the old copper mines of Roua (Alpes-Maritimes, France), associated with pecoraite, vesignieite, olivenite, kolfanite, janggunite, chlorargyrite, cuprite, native copper, native silver, native silver containing 2 % of mercury, domeykite, djurleite and algodonite. It forms aggregates (0.2 mm diameter) consisting of pseudooctahedral crystals (50 μm maximum dimension). The crystals are red, brownish red. The mineral is tetragonal, I 4, a = 7.727(7) A, c = 4.648(5) A, V = 277.5(5) A 3 , Z = 2 and D calc = 7.733(3) g/cm 3 . The strongest lines in the X-ray powder diffraction pattern (d obs in A, (hkl), I VIS ) are: 5.45, (110), 25; 2.772, (211), 100; 2.324, (002), 30; 2.254, (301), 20. Luster is adamantine translucent, streak is brownish red; crystals are uniaxial(+) with ω ∼ 2.3, ϵ ∼ 2.5 at 589 nm. Pleochroism is intense with ϵ = red orange intense, ω = orange brown. The crystal structure was solved from data collected using synchrotron radiation by traditional direct methods and refined using 350 observed unique reflections to R (F) = 0.037, Rw (F 2 ) = 0.075. The structure of tillmannsite containes isolated tetrahedra (V, As)O 4 and tetrahedral clusters (Ag 3 Hg) formed by metallic atoms. Each (Ag, Hg) metallic atom is coordinated by 3 metallic neighbors and by 3 oxygens.

Behavior of chemically modified cellulose towards dyeing. IV. Dyeability of poly(methyl vinyl pyridine)-cellulose graft copolymers before and after treatment with epichlorohydrin

Grafting of 2-methyl-5-vinyl pyridine (MVP) onto partially carboxymethylated cotton having 6 meq COOH/100 g cellulose (PCMC) was effected by a Fe2+-H2O2 redox system. Different graft yields were obtained by varying MVP concentration from 10 to 100 wt % PCMC. In a subsequent step these graft copolymers were treated with epichlorohydrin. Dyeing of untreated cotton, PCMC, PCMC grafted with MVP, and epichlorohydrin-treated poly(MVP)-PCMC graft copolymers was carried out at room temperature (27°C) for varying lengths of time (2.5–60 min) in the absence of alkali catalyst or any other additives. Three reactive dyes, Procion Red M-GS, Procion Orange Brown H-2GS, and Remazole Brilliant Blue; a direct dye, Orange Solophenyle 2RL; and an acid dye, Erio Blue Marine 2GR were used at a concentration of 2% by weight of material. It was found that none of the three reactive dyes or the acid dye interacts with untreated cotton or PCMC. In contrast, the direct dye did. PCMC grafted with MVP, on the other hand, showed a substantial extent of dye exhaustion regardless of the dye used. After-treatment of poly(MVP)-PCMC graft copolymers with epichlorohydrin significantly enhanced the extent of dye exhaustion. The latter reacted almost 100% with all the dye examined, irrespective of the graft yield, which varied from 1.6% to 63%. Dyeings for reactive dyes withstood soaping for 1 hr at boil and extraction with 50% dimethylformamide, whereas dyeings for the direct dye and the acid dye failed to do so. It is believed that the presence of pyridine moieties in the graft act as an internal, built-in catalyst for expediting the reaction of reactive dyes with cellulose hydroxyls and behave as a weak base capable of salt-linkage formation in case of the acid and direct dyes.