bluuebunny/crossref_metadata_2025 huggingface dataset:
On a new barium plagioclase felspar
Authors: Nockolds S. R. , Zies E. G.
Published: December 2006

In the memoir dealing with the geology of the Broken Hill district, New South Wales, mention is made 1 of a remarkable rock type found in a few places in the vicinity of Broken Hill, which looks not unlike an aplite in the field. A brief description of its appearance in thin section is given. It consists mainly of what appears to be very basic plagioclase. A fair amount of quartz, some epidote and bluishgreen hornblende were noticed, whilst a notable amount of sphene is present.
Some relationships between the reflectivities of sulphide ore-minerals
Authors: Coles Phillips F.
Published: December 2006

Since the early work of Dmde and others on the reflection of light by opaque crystalline media, little progress has been made in the direct determination of the indices of refraction and absorption for such substances. Interest in the optical properties of the opaque minerals, however, has been greatly stimulated by the rapid development in the last few years of the methods of ore-microscopy first brought into prominence by Campbell in 1906. Full theoretical discussions have been given recently by Berek, Koenigsberger, and others, but the only quantitative measure feasible in routine microscopy at present is that of the reflectivity.
Lusakite, a cobalt-bearing silicate from Northern Rhodesia
Authors: Skerl A. C. , Bannister F. A.
Published: December 2006

This interesting new mineral was discovered by the first author in February 1933 whilst in the employment of the British South Africa Company Limited as a field geologist to the Rhodesia Minerals Concession Limited under the direction of Dr. J. Austen Bancroft. The locality, longitude 29° 29′ E. and latitude 15° 27′ S., is about eighty miles east of Lusaka, the new capital of Northern Rhodesia, after which the mineral is named. The central African plateau has here been cut back from the northern escarpment of the Zambezi rift valley, about 10 miles to the south, producing a rugged topography varying from 1,000 feet to 4,000 feet in altitude.
On paratacamite and some related copper chlorides
Authors: Frondel Clifford
Published: December 2006

In the course of a study of the corrosion products formed by seawater sprayed at a temperature of 85° F. on brass and copper sheets, a pale green compound was isolated which proved on chemical analysis to have the composition Cu2(OH)3Cl. The X-ray powder diffraction pattern of the substance was found on visual comparison to differ from that of atacamite, which has the same chemical composition. The atacamite pattern was obtained from a specimen of the mineral from Moonta, on the u peninsula, South Australia, that had been authenticated by both morphological measurement and optical study; identical patterns were obtained from a number of other specimens labelled atacamite. The pattern of the corrosion product proved to be identical, however, with that of two specimens in the Harvard collection labelled paratacamite. These were labelled as from Remolinos, Vallinar, Chile (no. 97523), and from Sierra Gorda, Chile (no. 82883).
Pisanite from Parys Mountain, Anglesey
Authors: Bor Leslie
Published: December 2006

During the Manchester University's 1946 geological excursion to Anglesey, a visit was made to Parys Mountain. At this locality small quantities of an attractive light blue mineral were found capping pyrite veins and in clefts in the rock. Larger finds were obtained in an artificial cavern which extended for fifty or sixty feet into the south-east side of the excavated pit. A specimen weighing 2½ pounds and consisting of silicified shale veneered with the pale blue mineral was collected by the author and examined in the geological research laboratory at Manchester University during the session 1948–1949. The blue mineral was identified as pisanite, and this is the first record of pisanite as a British mineral.

Parys Mountain is situated in the north-west of Anglesey close to Amlwch. Copper and to a smaller extent lead were mined throughout a period exceeding one hundred and fifty years, but operations have completely ceased since the first world war. The geological structure of the district need only be briefly outlined for the purpose of this study.
Dichroscopes for microscope stage and ocular
Authors: Dollar A. T. J.
Published: December 2006

The optical accessories here described are two dichroscopes to facilitate microscopical comparisons by eye between the hues and intensities of axial absorption colours shown by thin slices, crushed fragments, or detrital grains of transparent coloured doubly-refracting crystals. Their chief applications lie in microscopic mineralogy and petrology, but they can be of service, also, in chemistry and allied subjects.

The aims of the accessories are two in number. They provide: (i) simple microscopic means for viewing simultaneously any pair of distinct hues, intensities of hue, or combinations of these variables, which result from differential absorption of white light; and (ii) a convenient method for detecting small differences between any pair of hues, intensities, or both, in terms of immediate ocular comparison between two sets of small symmetrically-shaped coloured images which alternate, and meet in straight boundaries.
L. J. Spencer's work at the British Museum
Authors: Campbell Smith W.
Published: December 2006

Leonard James Spencer, Keeper of Minerals in the British Museum (Natural History) from December 1927 to July 1935, joined the Department of Mineralogy officially on January 1, 1894, filling a vacancy caused by the death in 1892 of Thomas Davies. Davies had served in the Department since 1857. Trained by Nevil Story- Maskelyne, Keeper from 1857 to 1880, he had taken a great share in the arrangement and labelling of the mineral collection and in his later years had also had charge of the collection of rocks. Spencer was almost equally well qualified as a petrologist and as a mineralogist. He had studied chemistry at the Dublin Royal College of Science before going to Cambridge, where he studied geology as well as mineralogy and chemistry and gained the Harkness Scholarship for Geology in 1893. The examination for the vacancy at the Museum was held in August 1893 and Spencer was the successful candidate.
Angular relations between equivalent planes and distances between equivalent points in symmetrical point groups
Authors: Niggli Paul
Published: December 2006

A fundamental problem arising out of the study of symmetrical point groups can be formulated as follows: Let N points in threedimensional space be connected two and two in every possible way by straight lines: what relations must exist between the lengths of these lines if the points are equivalent members of a symmetrical point group ?

The methods of projection used in crystallography (e.g. the stereographic projection) at once show that the points may be considered to be the images of straight lines or planes. The problem formulated above has therefore a direct application to descriptive crystallography and can in this connexion be stated as follows:

A complex of N planes is determined by the points of intersection of the normals with the surface of a unit sphere, i.e. by their poles. What now must the angular relations between the planes be if all are equivalent, that is to say, belong to one and the same simple form ?
The Breece, New Mexico, meteoritic iron
Authors: Beck Carl W. , LaPaz Lincoln , Goldsmith Louis H.
Published: December 2006

The literature of meteoritics contains little information about the unusual Breece meteorite. This iron appears to be mentioned only in museum accession reports and catalogues of meteorite collections, and the sole information supplied by these references consists of the approximate date of find (1921), the approximate weight (50 to 51 kg.), the approximate place of discovery, near Breece, McKinley County, New Mexico, in latitude 35° 18' N., longitude 108° 18' W., and the classification (Ore). At the time of the discovery the hamlet of Breece was the centre of a small lumbering industry, since moved SW. and SE. into more heavily forested areas, and today it has few inhabitants. The find consisted of a single well-preserved mass which was purchased in its entirety from an unnamed source by the Field Museum of Chicago approximately ten years after the iron was discovered.
Studies in felspar equilibria at the Geophysical Laboratory, Washington
Authors: Tuttle O. F.
Published: December 2006

Evidence for the existence of four series of alkali-felspars has been obtained from X-ray studies of over forty analysed felspars.1 Optical studies confirm these findings, but suggest that transitional forms may occur. The four series are: high-sanidine- high-albite; sanidine high-albite; orthoclase low-albite;microcline-low-albite. Highsanidinc has the optic axial plane parallel to (010) in the potash-rich members, whereas it is perpendicular to (010) in sanidine.
Taaffeite, a new beryllium mineral, found as a cut gemstone
Authors: Anderson B. W. , Payne C. J. , Claringbull G. F.
Published: December 2006

In October 1945 Count Taaffe, a brilliant if unorthodox Dublin gemmologist, in the course of examining a motley collection of gemstones, came across a small mauve stone which puzzled him greatly. The stone had the appearance, and most of thc characters, of spinel, but afforded clear evidence of double refraction. As recounted below, this stone was later found to belong to an entirely new mineral species-—the only case hitherto known where a mineral has been first encountered as a faceted gem.
The amygdale minerals in the Tertiary lavas of Ireland. I. The distribution of chabazite habits and zeolites in the Garron plateau area, County Antrim
Authors: Walker George P. L.
Published: December 2006

The origin of the zeolites and associated minerals in vesicles in lavas is a subject on which there is considerable difference of opinion. In general there are two main views: that they are due to the action of percolating surface waters upon thc original minerals of the rock; or are associated with some stage of the cooling processes, as an after-effect of volcanism.
The graphitization of diamond and the nature of cliftonite. (With Plate XXVI)
Authors: Grenville-Wells H. J.
Published: December 2006

It has long been known that if a diamond is heated in pure oxygen, or even in air, to a temperature of about 700° C. or higher (depending on the initial quality of the diamond), it will be wholly or partially oxidized to CO or CO2, but that if the diamond is heated in the absence of oxygen—preferably in vacuo—to a temperature of about 1500° C. or higher (again depending on the initial quality of the diamond), it will be wholly or partially converted to graphite. For complete conversion the graphite is always poly crystalline. The partial conversion of diamond to graphite is, however, of considerable interest, because when graphite forms on a single crystal of diamond it exhibits a strong preferred orientation.
Textural features of some Bushveld norites
Authors: Wells Alfred Kingsley
Published: December 2006

Geophysical Laboratory work is especially applicable to quenched rocks, but does not lend itself to the solution of problems connected with the interpretation of structural relationships between the component minerals of deep-seated rocks. The detailed examination of a rock of simple mineral composition might be expected to yield a picture of the way in which phase-boundary adjustments are made in a rock crystallizing under such conditions. Some of the Bushveld basic rocks are of such a nature, and in the present paper an attempt is made to analyse and interpret the structural relationships between the two minerals bronzite and bytownite (An78-80), of which they are composed. The material studied was collected under the guidance of Dr. A. L. Hall during the International Geological Congress in 1929, supplemented by core specimens recently made available through the courtesy of an old student of the College.
The unit cell and space-group of alamosite (PbSiO3)
Authors: Mackay A. L.
Published: December 2006

Alamosite was first described by Palachc and Merwin, i who thought it might be isomorphous with wollastolfite. For that reason it has been re-examined, using X-ray methods.

A specimen from the original locality at Alamos, Sonora, Mexico (B.M. 1910,330) was made available through the courtesy of the British Museum (Natural History), and in physical appearance it tallied with the original description. The crystals were aggregates of fibres arranged in bundles which cleaved perfectly perpendicular to the fibre axes. Small tablets could be readily cut out for X-ray analysis. The refractive indices were very high and the dispersion was large. As the axial ratios found by X-ray methods agreed with those given by Palache and Merwin, the latter's chemical analysis and density determination were not repeated.
Synthetic soda-free thomsonite
Authors: Goldsmith Julian R.
Published: December 2006

X-ray powder photographs reveal thomsonite a.s the principal product of some low-temperature hydrothermal experiments. Glasses of three compositions were used as starting materials; one of tile composition of anorthite (CaAl2Si2O8), one of a gallium-containing anorthite (Ca4[Ga3Al5]Si8O32) in which 3/8 of the Al is replaced by Ga, and a glass of the oxide composition of zoisite minus the water (4CaO. 3Al2O3. 6SiO2).
Okenite and nekoite (a new mineral) (With Plate I.)
Authors: Gard J. A. , Taylor H. F. W.
Published: December 2006

The unit cell of okenite (CaO.2SiO2.2H2O) has been determined for a specimen from Bombay, India, using a combination of X-ray, electron-microscope, and electron-diffraction methods. It is anorthic with a 9·84, b 7·20, c 21·33Å., α 90·0°, β 103·9°, γ, 111·5°, elongation b, Z 9. These data are compatible with the goniometric results of Boggild (1922) and allow the latter to be interpreted.

A specimen from Crestmore, California, which Eakle (1917) had described as okenite, was also examined. It was found to be a new species, having the same composition as okenite but distinguishable from it by its optical properties, X-ray powder data, and unit cell. The latter is anorthic with a 7·60, b 7·32, c 9·86 Å, α 111° 48′, β 86° 12′, γ 103° 54′, elongation b, Z = 3. Because of the relation to okenite, the name nekoite is suggested.
On the correlation of physical properties with chemical composition in multivariate systems
Authors: Hey Max H.
Published: December 2006

A systematic and time-saving procedure for the correlation of optical or other physical properties with chemical composition is outlined, and is applicable even where the composition is complex and involves several variables. The procedure is applied to anthophyllite, for which the following partial regression equations are derived:

γ = 1·7249−0·0130Si+0·0140(Ti+Fe‴+Fe′+Mn)±0·0012,

β = 1·7275−0·0142Si+0·024(Ti+Fe‴)+0·0110(Fe″+Mn)±0·0015,

α = 1·6951−0·0117Si+0·040(Ti+Fe‴)+0·0133(Fe″+Mn)±0·0025,

b(Å.) = 16·44+0·28Si−0·13Mg+0·40(Ca+Na+K)±0·04.

The a and c cell-dimensions appear to be constant, within the experimental error of the available data.
Replacements involving early carnallite in the potassium-bearing evaporites of Yorkshire
Authors: Stewart F. H.
Published: December 2006

Evidence from four recent boreholes in the Yorkshire potash field suggests that carnallitic was an important original constituent of the Middle Evaporite Bed, and that much of the sylvine of the potash zone is of secondary origin.

The carnallitie rocks have been affected by complex replacements, an earlier series involving sylvine, halite, and anhydrite, and a later series involving rinneite, halite, sylvine, and carnallitic.
Staurolite twinning (With Plates V-VI.)
Authors: Hurst Vernon J. , Donnay J. D. H. , Donnay Gabrielle
Published: December 2006

The space group Ccmm of the accepted staurolite structure (7·82:16·52:5·63 kX 0·473:1:0·341, Náray-Szabó 1929) is a pseudo-space group; the true one has no c glide plane. Staurolite is monoclinie pseudo-orthorhombic, as shown optically by horizontal dispersion and morphologically by unequal developments of forms r(201) and r′(01). It has variable cell dimensions, 7·83–7·95:16·50–16·82:5·62 5·71 Å., constant β 90° + 3′, aspect C*, and probable space group C2/m (negative pyroelectric test). This leads to the prediction of a new type of twin, ‘by high order merohedry’, a penetration twin that simulates an orthorhombic single crystal. It is known (Friedel, 1922) that the 90°-cross can be accounted for by two different twin laws and the 60°-cross by five. The twin operations are respectively the pseudo-symmetry operations of a pseudo-tetragonal cell, obtained by transformation 010/003/100, and those of Mallard's pseudo-cube, resulting from transformation 013/03/300. By precession methods more than one twin law is established for each type of cross: both laws [100]90° and [013]180° are found for 90°-crosses: [313]180 and [102]120°, for 60°-crosses.
Experimental and theoretical studies of the mica polymorphs
Authors: Smith J. V. , Yoder H. S.
Published: December 2006

An experimental and theoretical study has been made in order to determine the number and the structure of the possible polymorphs and to determine the structural relations between them. The simplest structures are 1M, 2M1, 2M2, 3T, 20, and 6H polymorphs, and more complicated types can be developed. Some of the previously described polymorphs were not contained in the theoretical list and were re-examined. The 6M structure was found to be a 2M2polymorph, the 6-layer triclinic type was found to be a 2M1polymorph, and the 3M structure was shown to be a 3T type. The 24-layer triclinic structure could be described on a simpler 8-layer cell. This type together with a new 12-layer monoclinic structure, as well as other structures of higher periodicity, presumably consists of complex stacking and results from spiral-growth mechanism. Two extreme types of layer-disordered crystals may be built and a disorder of individual ions may also occur. Single stacking faults result in twinned crystals. A new twin relation (180° rotation about the [100] axis) has been recognized. Twenty specimens from extreme geological environments have been examined in order to evaluate the control of environment on the stacking. The type of stacking could not be attributed solely to the influence of pressure and temperature. Composition appears to play a dominant role in the type of stacking, and semi-quantitative structural arguments appear to support this contention. The influence of growth mechanism is discussed. A scheme for the identification of the mica polymorphs by X-ray powder and single-crystal methods is given.
A case of epitaxic replacement
Authors: Kostov Ivan
Published: December 2006

Quartz from a granite pegmatite near Kalkovo, Bulgaria, has undergone partial replacement by biotite along cracks parallel to (01;0); the biotite is in regular orientation relative to the quartz, and appears to constitute an instance of epitaxic replacement, defined as a replacement in which the replacing mineral develops in a regular, structurally controlled orientation relative to the mineral replaced.
Kingite, a new hydrated aluminium phosphate mineral from Robertstown, South Australia
Authors: Norrish K. , Rogers Lillian E. R. , Shapter R. E.
Published: December 2006

A new hydrated aluminium phosphate mineral,kingite, from phosphate workings near Robertstown, South Australia, has an idealized formula Al2O3.Al(OH)3.P2O5.9H2O, with some replacement of OH by F. The specific gravity is 2·2 to 2·3, refractive index 1·514, and percentage chemical composition Al2O331·92, P2O528·63, H2O 37·93. The three strongest lines on the X-ray diffraction pattern are 9·1, 3·45, and 3·48 Å. Kingite changes to a less hydrated phase between 154° C. and 163° C., which is also considered to be a new aluminium phosphate (meta-kingite) with idealized formula Al2O3.Al(OH)3.P2O5.4H2O. The strongest lines of its X-ray diffraction pattern are at 7·4, 5·02, and 37·19 Å.
Measurement and distribution of zircons in some granitic rocks of magmatic origin
Authors: Larsen Leonard H. , Poldervaart Arie
Published: December 2006

Morphological characters of zircons in concentrates have been studied by measurement of length along the c-axis and breadth along the a1- or a2-axis of 200 doubly terminated crystals for each sample. The sample is represented graphically by a line fitted mathematically to a scatter plot of the measurements. This line, the reduced major axis, is visualized as a growth trend, and samples are described and compared statistically.

From a careful study of zircons in a tonalite it is concluded that zircon crystallized over a short range before crystallization of the main constituent minerals.

The distribution of zircon in a batholith of magmatic origin has also been studied. The batholith grades from a core of granodiorite to a mantle of tonalite, but the zircons are uniform throughout. Small bodies of granodiorite and quartz monzonite have sharp contacts against the main batholithic rocks, and zircon samples from these intrusives differ from one another and from those of the batholith. It is concluded that the batholith represents a single intrusion which differentiated after emplacement, and that the later intrusives each crystallized under different conditions.
Rare earths in some niobate-tantalates
Authors: Butler J. R.
Published: December 2006

Rare-earth distribution has been determined for fourteen niobatetantalates containing essential rare earths. Those minerals with more than about 15 % TiO2 (and corresponding to either priorites or members of the euxenite-polycrase series) have Yt as the dominant rare earth with the heavier lanthanons in excess of the lighter lanthanons. Those minerals with less than about 4 % TiO2 and less than about 30 % (Yt,Ln)2O3 (and corresponding to samarskites) also have Yt as the dominant rare earth but they show a marked concentration of Gd + Tb + Dy over the other lanthanons. It is tentatively suggested that this power of selective lanthanon enrichment may be characteristic of samarskite among the niobate-tantalates examined.
Heat treatment of metamict euxenites, polymignites, yttrotantalites, samarskites, pyrochlores, and allanites
Authors: Lima-de-Faria J.
Published: December 2006

The standard thermal treatments proposed by Lima-de-Faria have been applied to metamict euxenites, polymignites, yttrotantalites, samarskites, pyrochlores, and allanites. In the case of these metamict niobotantalates a facecentred cubic phase is formed at 700° C., and at 1000°C. a more characteristic phase appears combined with the cubic one. In the case of allanites only a slight formation or strengthening of the original structure of allanite appears at 700°C., and at 1000°C. a cubic phase is formed together with other phases.
A hydrated barium-strontium pyrochlore in a biotite rock from Panda Hill, Tanganyika
Authors: Jäger E. , Niggli E. , Van der Veen A. H.
Published: December 2006

A hydrated barium-strontium pyrochlore with only subordinate amounts of Ca and Na has been found in a weathered biotite rock (contact-rock of a carbonatite) from Panda Hill, Tanganyika, as small euhedral yellowish-grey cubic crystals (showing the combination of the octahedron and the cube) in a rock containing euhedral biotite, some orthoclase, and several other minerals. Hydrated Ba-Sr pyrochlore is isotropic, the refractive index varies from 2·07 to 2·10. The reflectivity (vertical illumination) is 13·2 %. H. Poor {111} cleavage. The pyrochlore structure (space-group O7h–Fd3m) and the unit-cell dimensions (a 10·562 Å.) are derived from X-ray powder and Weissenberg photographs. The calculated specific gravity is 4·01 (observed, 4·00 on dried material). Chemical analysis gives BaO 12·5, SrO 6·4, Na2O 0·28, K2O 0·25, CaO 1·35, rare earths (mainly Ce2O3) 2, ThO2 0·6, FeO 0·45, TiO2 3·9, Nb2O5 67·0, Ta2O5 0·22, H2O+ 4·0, other constituents 2·21, total 101·16. After deduction for impurities the following formula resulted: (Ba0·30Sr0·22Ca0·05Ce0·04Na0·03Fe0·02K0·01Th0·01)(Nb1·83Ta0·004Ti0·17)O5·61(H2O)0·80.

The ideal formula for pyrochlore is A2B2O6(F,OH). In the mineral described only a third of the A-positions are occupied by Ba, Sr, etc. Infra-red spectrophotometry does not indicate hydroxyl-groups. When the mineral is treated with TINO3 solution the intensities of the X-ray diffraction lines 333/511, and 444 are changed; hydrated Ba-Sr pyrochlore shows a certain exchange-capacity.

The name pandaite, from Panda Hill, is proposed for the new mineral.
A new method for thermal dehydration studies of clay minerals
Authors: Kulbicki Georges , Grim Ralph E.
Published: December 2006

The water vapour released upon heating the specimen is driven through a water absorber. The intensity of the exothermic reaction produced by absorption of the water is recorded against the temperature of the specimen. A series of curves obtained with various clay minerals are presented to illustrate the method. The significance of results in the identification of the clay minerals and the determination of their structure is considered.
The ageing of sesquioxide gels. I. Iron oxide gels
Authors: Mackenzie Robert C. , Meldau Robert
Published: December 2006

The gels prepared by adding ammonium hydroxide rapidly to ferric chloride solutions to various pH values are shown to consist of amorphous material and crystalline goethite ; no other iron oxide was definitely identified in the present experiments, although this does not preclude other oxides being present in gels prepared under slightly different conditions. The goethite grows as acieular crystals on ageing at all pH values, but the rate of growth is greater at higher pit values. The exothermic peaks appearing on differential thermograms of such gels are apparently due to coalescence of extremely minute hematite particles to give larger particles, the sharpness of the peak indicating to some extent the size of the original hematite particles. These observations are related to data for other iron oxides, and the morphology of ferric oxide polymorphs under the electron microscope is considered.
Recent secondary minerals in the Billingham anhydrite mine
Authors: Raymond L. R.
Published: December 2006

A number of secondary minerals have grown in recent years in a part of the Billingham anhydrite mine, by evaporation of water from the Upper Magnesian Limestone, and include some unusual species, the most interesting of which is thought to be ilsemannite.
Electron-optical data for crystals of scarbroite
Authors: Brindley G. W. , Comer J. J.
Published: December 2006

Electron micrographs of scarbroite show thin platy crystals of about 1 μ size, having rhombic outlines with angles 66° ± 1° and 113° ± 1°. Single-crystal electron-diffraction patterns show rectangular net patterns, with d100 = 9·90 Å., d010 = 14·67 Å., γ* = 90° ± 0·05°. Strong hk0 reflections show a pseudohexagonal arrangement, but true symmetry is probably orthorhombic or monoclinic. Faces outlining rhombic forms are of type {11l}, .
A possible explanation of immiscibility in silicate melts
Authors: de Wys E. Christiaan
Published: December 2006

The problem of silicate immiscibility, of petrological and technological interest, is discussed in terms of the structures of silicate crystals and certain phase diagrams. Physical chemical principles are employed to indicate the author's basis for suspecting that certain structures in the crystalline solid are carried over into the melt and are a major contributory cause of silicate immiscibility. These structures appear to be limited to the neso (SiO4)4−, soro (Si2O7)6−, cyclo (Si3O9)6−, and ino (SiO3)2− types of silicate polymers and do not include the more complex phyllo- and tecto-silicate polymers.
β-Ferric Oxyhydroxide
Authors: Mackay A. L.
Published: December 2006

The crystallographic properties of the hydrated iron oxide obtained by the hydrolysis of FeCl3 are described. The characterizing X-ray powder pattern can be indexed on a tetragonal unit cell with a 10·48 and c 3·023 Å. This cell is shown to contain eight formula units of FeOOH but Cl- or other anions are necessary for the crystallization of the material The structure is that of hollandite or α-MnO2. The unit cell has been confirmed by electron diffraction from single crystals having dimensions about 5000 × 500 × 500 Å. and twinning, which produces hexagonal stars, has been studied. On heating, the structure breaks down and recrystallizes as α-Fe2O2, probably with an intermediate stage involving a spinel phase.
A thermal study of thaumasite
Authors: Font-Altaba M.
Published: December 2006

A differential thermal analysis curve of thaumasite shows an endothermal peak at 206° C., correspinding to the loss of H2O and CO2, and a weak exothermal peak at 709° C., corresponding to recrystallization to a mixture of anhydrite and larnite, as is shown by X-ray powder photographs of material heated to 950° C. Improved powder data for thaumasite are given: the three strongest lines are at 9·66, 3·79, and 4·58 Å., and the cell-dimensions are a 10·992, c 10·311 Å.
Magnetic susceptibility of garnet
Authors: Frost M. J.
Published: December 2006

The mass suseeptibility of 23 analysed or partially analysed garnets has been measured by means of a calibrated Franz Isodynamic magnetic separator. Straight lines are fitted to the adjusted data for mass susceptibility and molecular composition. The mass susceptibilities of the theoretical end-members in electromagnetic units × 106 are estimated as: almandine, 68±2 e.m.u.; spessartine, 81±3 e.m.u.; and andradite, 49±3 e.m.u. Grossular and pyrope are assumed to have susceptibilities of nil.
Silicate melts with indications of ino structures
Authors: de Wys E. Christiaan
Published: December 2006

Evidence is presented for the existence of silicon-oxygen chains up to 1000 Å. in length in melts of CaMgSi2O6 and of LiAISi2O6 at temperatures a little above the melting point.
The cummingtonite problem
Authors: Layton W. , Phillips R.
Published: December 2006

An examination of available chemical analyses shows that the anthophyllite and cummingtonite series of amphibole minerals are not isodimorphous. Whilst the anthophyllites are truly lime-free amphiboles, small amounts of calcium are essential to stabilize the monoclinic lattice of cummingtonites, which should be regarded as lime-poor amphiboles, analogous to the lime-poor pyroxenes. The existence of synthetic clino-anthophyllites is considered.
A galena-wulfenite-uraniferous-asphaltite horizon in the Magnesian Limestone of Nottinghamshire
Authors: Deans T.
Published: December 2006

The top 2 inches of the Lower Magnesian Limestone is feebly but persistently mineralized along its outcrop from Nottingham to Doncaster, predominantly with galena and a little cerussite, frequently with uraniferous asphaltite containing 0·2 to 1% U3O8. Wulfenite, both platy and pyramidal in habit, occurs at Bulwell and Kirkby in Ashfield. The mode of formation and the age of these minerals are discussed.
Djurleïte from Calabona, Sardinia
Authors: Bernardini G. P. , Corsini F. , Tanelli G.
Published: December 2006

Djurleïte has been identified by X-ray analysis in a sample from Calabona, Sardinia. Morphological characteristics, chemical composition, and thermal behaviour (studied by high temperature X-ray analysis and D.T.A.) are reported. Chemical composition and breakdown products upon heating differ from those of synthetic djurleïte in the Cu-S system.
Chemical variation in minerals of the astrophyllite group
Authors: Macdonald R. , Saunders M. J.
Published: December 2006

Eight new and fourteen published analyses of astrophyllites are used to examine chemical variation within the group. Al, Ca, Cs, F, Mg, Mn, Nb, Rb, Sn, Zn, and Zr may all substitute in moderate to large amounts in the unit cell, whose basic formula is (K,Na)3Fe7Ti2Si8(O,OH)31; the natural Mn- and Nb- analogues of astrophyllite have been recorded. Ba, Cl, Cu, Li, P, Pb, Sr, and Ta are present, but in smaller amounts. The majority of specimens show appreciable cation deficiencies, up to 5 % of sites remaining vacant. Astrophyllites from undersaturated igneous rocks are characterized by higher Al, Ca, Mg, Mn, (OH+F), (K+Na) and Zr, and lower Li, Pb, and Zn contents than those from oversaturated igneous rocks. A ‘high-alkali’ type of astrophyllite is distinguished. A new occurrence of nigerite is noted.
Low-iron cordierite in phlogopite schist from White Well, Western Australia
Authors: Pryce M. W.
Published: December 2006

Pale-blue cordierite (complete analysis given; shows total iron oxides only 0·98 %) occurs in phlogopite schist near White Well (24° 28′ 30″ S. 116° 2′ E.) 20 miles north-west of Yinnietharra, Western Australia. Associated minerals are corundum, dravite, and sillimanite, accessory zircon and rutile. The cordierite is in translucent masses to 8 ×8×4 cm with vitreous lustre, D 2·57, α 1.536, β 1·540, γ 1·543, all colourless, 2Vα80° Unit cell a 17·055, b 9·724, c 9·350 Å. The host phlogopite (complete analysis given) is in brown flakes to 1 cm, D 2·88, α 1·558, β 1·585, γ 1·59, 2Vα 5–20° 1 M polymorph.
Chemical weathering on the Carnmenellis
granite
Authors: Rice C. M.
Published: December 2006

The behaviour of 25 major and trace
elements, together with mineral changes, has been
examined in a deep weathering profile on the
Carnmenellis granite, Cornwall. The bulk chemical
and mineralogical composition of the regolith
shows only minor changes from the parent rock
indicating a low degree of chemical weathering.
However, within the regolith marked differences
occur between the fine fractions from the various
horizons. Chlorite and degraded muscovite
characterize the fines of horizons
A+B
and C whereas gibbsite
and kaolinite characterize horizon
D. Secondary minerals
becoming base deficient with depth is the reverse
of normal behaviour and two possible theories are
advanced to explain this anomaly. Most of the
trace elements are concentrated in the < 10 µm
fraction of the various horizons, in part by an
association with degraded muscovite. Tin and Zr
occur in resistates and Be, Sr, and Co are mainly
lost during weathering.
Stratigraphical etch patterns on the
rhombohedral cleavages of natural quartz
crystals
Authors: Joshi M. S. , Paul Baby K.
Published: December 2006

Rhombohedral cleavage faces of quartz have
been etched hydrothermally and with fused KOH.
Stratigraphical etch patterns were observed on
isolated cleavages, matched cleavage faces, and
opposite sides of a thin flake. The angle between
the ()
cleavage plane and the planes responsible for the
stratigraphical patterns was almost equal to the
interfacial angle, 46° 16′ between adjacent
rhombohedral faces. It is concluded that the
stratigraphical patterns formed by preferential
etching reveal the edges of weak planes deposited
during growth. The implications are
discussed.
Carbonate enrichment at the margins of a basic dyke, Ardnamurcha
Authors: Wells M. K. , Smith A. C. S. , Bowles J. F. W.
Published: December 2006

A gradational increase in concentration of CO2 towards the margins of a very fine-grained basalt dyke has led to the development of a pale marginal facies, enriched in carbonates, particularly siderite. Increases in CO2 from about 3 % in the interior of the dyke to 8 % at the margins are accompanied by decreases in SiO2 and Fe2O3, increases in Al2O3, and less significant changes in the other major components. Cu, Co, and Zn change only slightly, and Cr, Ni, and Li remain constant. Petrographic variation is considerable, even in the superficially homogeneous interior of the dyke, in which it ranges from a type containing a titanaugite (analysed) to one devoid of pyroxene, but containing conspicuous opaque minerals. Microprobe analysis for Fe and Ti shows that these comprise: cotahedral titaniferous magnetite; rodlets, less than 1 µm thick, of rutile partly altered to, or overgrown by, ilmenite; and sub-opaque patches with a very low Ti/Fe ratio. Plagioclase, An55, is the most abundant and constant crystalline phase in the interior of the dyke, but changes to An20 in the marginal facies. Mineral-content of the latter, deduced from optical, chemical, and X-ray data, also includes siderite, serpentine and clay minerals, leucoxene, and apatite. There is no evidence of quartz, sericite, or calcite.

Petrographic evidence shows that variations in concentrations of CO2 and H2O affected phase equilibria from the start of magmatic crystallization. Data on the fO2 required for TiO2 and Fe-oxide phases to co-exist at magmatic temperatures indicate that, initially, the concentrations of CO2 and H2O in the interior of the dyke were higher than the values recorded in analyses of the rocks. From this evidence and the field relationships, it is concluded that the intruding magma was rich in volatiles, which diffused towards the dyke margins and, in part, became trapped as the magma congealed, producing a changed marginal assemblage of minerals. The dyke provides a unique glimpse of influences on a basic magma exerted by what S. J. Shand has aptly termed the ‘fugitive constituents’, the transient effects of which are rarely preserved in the rocks.
Manganese minerals in geodes from Chihuahua, Mexico
Authors: Finkelman Robert B. , Evans Howard T. , Matzko John J.
Published: December 2006

Seven manganese minerals have been observed in geodes from Chihuahua, Mexico. Ramsdellite occurs in a number of different habits, but the morphology and precession X-ray patterns suggest that it is pseudomorphous after groutite. Pyrolusite is found only in association with rams-dellite and is believed to be an alteration product of that mineral. Todorokite generally occurs as a late-stage fibrous overgrowth in many of the geodes. Ranciéite, birnessite, hollandite, and cryptomelane are present in trace amounts. This assemblage of manganese minerals is typical of supergene mineralization.
Tantal-aeschynite, a new mineral of the aeschynite group from the Borborema region, north-eastern Brazil
Authors: Adusumilli Maria S. , Kieft C. , Burke E. A. J.
Published: December 2006

Tantal-aeschynite occurs as idiomorphic metamict crystals in the Raposa pegmatite at São José do Sabugí, Paraíba State, NE. Brazil. Morphological data, microscopic properties, and differential thermal analysis results are given. Electron-microprobe analyses yielded a formula: {Ca0·28(Yt,Ln)0·425(Th,U)0·11}(Ta0·75Ti0·62Nb0·595Fe0·05)O6. Yttrium is the predominant rare-earth element, with cerium and neodymium as most abundant lanthanides. The tantal-aeschynite unit cell has (after heating) a 5·34, b 10·97, c 7·38 Å. An indexed X-ray powder pattern (similar to that of aeschynite) is presented.
Magnesian collinsite from Milgun Station, Western Australia
Authors: Bridge P. J. , Pryce M. W.
Published: December 2006

An occurrence of magnesian collinsite has been found with other rare phosphates in a variscite deposit in semi-desert 15 km NW. of Milgun Station homestead (25° 6′ S., 118° 18′ E.), Western Australia. The collinsite occurs as tapering white 3-mm prisms, mammillated aggregates, and thin veinlets in cavities in mudstone. The crystals have two good cleavages, D2.93, subvitreous lustre, H4–5, white streak and are brittle. Optical properties α 1·632, β 1·642, γ 1·657, 2Vγ , ≈ 80°. The mineral is triclinic with a 5·734, b 6·780, c 5·441 Å, α97·29° β 108·56°, γ 107·28°. X-ray powder data given, the lines are similar to P.D.F. card 14–314 but new cell gives better indexing. Chemical analysis by F. R. W. Lindsey gave FeO 0·07, MgO 11·3, CaO 35·2, Na2O 0·01, K2O 0·02, P2O5 41·2, H2O+10·7, H2O− 0·15, F0·02, SiO2 (quartz impurity) 1·31, Al, Mn, Zn, SO3 not detected, net sum 99·97, close to Ca2Mg(PO4)2.2H2O, after deduction of moisture and quartz impurity. Typical specimens are preserved at the Government Chemical Laboratories, Perth, Western Australia.
High-iron bustamite and fluorapatite from the Broken Hill mine, New South Wales, Australia
Authors: Harada K. , Sekino H. , Nagashima K. , Watanabe T. , Momoi H.
Published: December 2006

High-iron bustamite and apatite occur as subhedral large crystals up to 1 to 2 cm wide and 10 cm long in close association with spessartine in the disseminated sphalerite- and galena-bearing diopside-roepperite-calcite skarn at the New Broken Hill Consolidated mine (N.B.H.S.), New South Wales, Australia. Complete chemical analyses of the minerals have been made, together with physical, optical, and X-ray studies.
Catalytic Asymmetric Synthesis and Optical Resolution of Planar Chiral Rotaxane
Authors: Makita Yoshimasa , Kihara Nobuhiro , Nakakoji Naohisa , Takata Toshikazu , Inagaki Shinji , Yamamoto Chiyo , Okamoto Yoshio
Published: December 2006

Planar chiral rotaxanes were synthesized from crown ether and secondary ammonium salt via trialkylphosphane-catalyzed acylative end-capping. Their optical resolution was achieved by chiral HPLC after acylative neutralization of the ammonium group. When optically active trialkylphosphane 2 was used as the chiral acylation catalyst, optically active rotaxane (4.4% ee) was obtained.
Turnover intention and performance in China: The role of positive affectivity, Chinese values, perceived organizational support and constructive controversy
Authors: Hui Chun , Wong Alfred , Tjosvold Dean
Published: December 2006

This study examines antecedents of turnover intention and job performance in China. The total sample consisted of 153 employees in a toy manufacturing factory in South China. Data from matched supervisor and subordinate responses supported the hypotheses that the workplace experience of perceived organizational support related to turnover intention which in‐turn related to individual job performance. Findings also indicated that the employees with traditional values and positive affectivity related significantly to perceived organizational support.
Understanding Consciousness Using Systems Approaches and Lexical Universals
Authors: Winkelman Michael
Published: December 2006

The numerous perspectives offered on consciousness reflect a multifaceted phenomenon that results from a system of relations. An etymological approach identifies linguistic roots of the meanings of consciousness and illustrates their concern with self‐referenced informational relationships of an organism with its environment, a "knowing system" formed in the epistemological relations between knower and known. Common elements of contemporary models suggest that consciousness involves interacting components of a system, including: attention‐awareness; phenomenal experiences; self reference; action‐behavior, including representations and learning; use of information; interpretation of meaning; goal‐directed behavior; and systems of social reference. It is suggested that manifestations of consciousness through the physical properties of the brain are universally represented in language. A preliminary systems model of consciousness is outlined with widespread lexical roots proposed as a culture‐neutral framework for constructing theories of consciousness and identifying cognitive constructs which reveal the epistemological roots of consciousness within Indo‐European traditions.
Effects of Inhalation Exposure to Propylene Oxide on Respiratory Tract, Reproduction and Development in Rats
Authors: Okuda Hirokazu , Takeuchi Tetsuya , Senoh Hideki , Arito Heihachiro , Nagano Kasuke , Yamamoto Seigo , Matsushima Taijiro
Published: December 2006

Effects of Inhalation Exposure to Propylene Oxide on Respiratory Tract, Reproduction and Development in Rats: Hirokazu Okuda, et al. Japan Bioassay Research Center, Japan Industrial Safety and Health Association—Nasal, respiratory, reproductive and developmental toxicities of propylene oxide (PO) were examined by exposing male and female Sprague‐Dawley rats to PO vapor by inhalation at a concentration of 0 (control), 125, 250, 500 or 1,000 ppm for 6 h/d, 7 d/wk, during a 5‐ to 6‐wk period, including premating, mating and postmating or gestation. The inhalation exposure to 1,000 ppm PO seriously affected parental survival, the upper and lower respiratory tract, male and female reproductive systems, motor function, and fetal survival and development, whereas the exposure to 500 ppm or less primarily caused nasal lesions without any sign of reproductive or developmental toxicity. Because atrophy of the olfactory epithelium in the male rats exposed to 250 ppm was the most sensitive endpoint for PO toxicity, the NOAEL was determined to be 125 ppm for the nasal endpoint. An additional inhalation experiment was carried out to further examine developmental toxicity by exposing pregnant rats to 0, 125, 250, 500, 750 or 1,000 ppm PO during a 2‐wk period of gestation, Day 6 through Day 19. The 2‐wk inhalation experiment revealed that reduced fetal body weights and delayed ossification occurred in association with significantly reduced body weights of the dams exposed to 750 and 1,000 ppm, whereas neither fetal death nor teratogenicity occurred at those two exposure levels. It was concluded that the developmental toxicity of fetal death was manifested at parentally toxic exposure levels above 500 ppm, a level which seriously affected parental survival, the upper and lower respiratory tracts and reproductive system.
Toxicity Study of the Volatile Constituents of Myoga Utilizing Acute Dermal Irritation Assays and the Guinea‐Pig Maximization Test
Authors: Wei Qingjun , Harada Koichi , Ohmori Shoko , Minamoto Keiko , Wei Changnian , Ueda Atsushi
Published: December 2006

Toxicity Study of the Volatile Constituents of Myoga Utilizing Acute Dermal Irritation Assays and the Guinea‐Pig Maximization Test: Qingjun Wei, et al. Department of Preventive and Environmental Medicine, Graduate School of Medical and Pharmaceutical Sciences, Kumamoto University—Myoga is a fragrant plant which is the special product of Japan and is cultivated throughout Japan. According to our earlier investigation (unpublished data) of myoga cultivators in Japan, 8 of 35 cultivators experienced contact dermatitis in the harvest season. The purpose of this study was to assess the allergenicity of myoga and its major volatile components. The volatile components of myoga were analyzed by gas chromatograph (GC). They included α‐pinene, β‐pinene and R‐(+)‐limonene. We performed a toxicity study of each of the major fragrant components of myoga using acute dermal irritation assays and the Guinea‐Pig Maximization test (GPMT) in order to probe the mechanism of allergic contact dermatitis. In acute dermal irritation assays, α‐pinene, β‐pinene and limonene showed positive responses at concentrations of 4%; limonene oxide at 20% and myoga showed a positive response at concentrations of 100%. From the results of the GPMT, according to Kligman scores, limonene oxide was identified as an extreme skin sensitizer and myoga as a mild skin sensitizer. The results of the present study show that R‐(+)‐limonene is the most important allergen amongst the chemical components of myoga, and we consider it to be the reason why myoga cultivators experience allergic contact dermatitis.