 | | Book | | PO Box 315. Harpenden. Hertfordshire AL5 2ZD. England Telephone: +44 (0)1582 762413 Fax: +44 (0)870 055.............................. 529 G: gadolinite group to gyrolite ......................... 226 X: xanthiosite...production of e0pper. the mining areas of Cornwall and Devon became important producers of b th tin and copp...further 154 species are unconfirmed. If all the group, series, variety and discredited species names are...1\llaga::i11e, on minerals from localities in Cornwall. Devon. Cumbria and Yorkshire. He was renowned for his |  | | Journal (volume) | | Tindle 23-25 PAPERS Danburite from Meldon Quarry, Okehampton and other UK localities Michael S. Rumsey, George...professional mineralogists and geologists both in the UK and overseas. One of the main aims of the Society...years ago the UK still had an active metalliferous mining industry, predominantly in SW England, and fluorspar...world class Hemerdon tungsten and tin deposit in Devon is forging ahead with the company focused on developing...interest in re-evaluating deposits in the north of England, and it has also been reported recently that the |  | Černý, Petr, Chapman, Ron, Ferreira, Karen, Smeds, Sten-Anders (2004) Geochemistry of oxide minerals of Nb, Ta, Sn, and Sb in the Varuträsk granitic pegmatite, Sweden: The case of an “anomalous” columbite-tantalite trend. American Mineralogist, 89 (4) 505-518 doi:10.2138/am-2004-0405 | Journal (article/letter/editorial) | | Consequently, the compositional trends of columbite-group minerals and cassiterite mimic those typically displayed...degree of cation order in the Varuträsk columbite-group minerals increases from early to late phases, and...approach to chemical equilibrium, but columbite-group inclusions in cassiterite show in part a compositional...whereas the more widespread pyrochlore-microlite metasomatic after columbite-group minerals reflects the Ta/(Ta...several grains of primary and metasomatic pyrochlore-group phases that also are enriched in Sb, but not |  | | Journal (article/letter/editorial) | | Feangereicherten Gliedern. Introduction Members of the pyrochlore group are probably the second most abundant Nb-...and alkalic rocks. Pyrochlore group minerals crystallize in the cubic space group-Fd3m, have unit cell..., 1986). The subdivision of the pyrochlore group into the pyrochlore, microlite and betafite subgroups...Microlite 85 Table 1. Classificationof the pyrochlore oroup minerals modified after Hogarth (1977)...Nb+Ta>2Ti & Nb>Ta Nb+Ta>2Ti & Ta>Nb 2Ti>Nb+Ta pyrochlore microlite betafite Ikalipyrochlore stannomicrolite |  | | Journal (article/letter/editorial) | | apparent reversal of Nb-Ta fractionation in columbite-group minerals from the Scheibengraben beryl-columbite...Compositional variation was studied in columbite-group minerals from the beryl-columbite pegmatite at Scheibengraben...units except the cleavelandite unit. Columbite-group minerals are the dominant Nb,Ta-oxide phases in...with other Nb,Ta-oxide minerals: minerals of the pyrochlore subgroup and fersmite in the coarse-grained unit...0.22) 0.35 to 0.90] fractionations in columbite-group minerals differ from those observed in beryl pegmatites |  | Baldwin, J. R., Hill, P. G., Finch, A. A., von Knorring, O., Oliver, G. J. H. (2005) Microlite-manganotantalite exsolution lamellae: evidence from rare-metal pegmatite, Karibib, Namibia. Mineralogical Magazine, 69 (6) 917-935 doi:10.1180/0026461056960299 | Journal (article/letter/editorial) | | Geodynamics Group, School of Geography and Geosciences, University of St Andrews KY16 9AL, UK Department...Edinburgh EH9 3JW, UK School of Earth Sciences, University of Leeds, Leeds LS2 9JT, UK ABS TR ACT We have...to the structure of pyrochlore (microlite). Hence, via the perovskite/pyrochlore analogy, hypothetical...manganotantalite-type structures may occur from a microlite (pyrochlore) host by solid-state diffusion via metastable...(1981) divided the orthorhombic columbite-tantalite group on the basis of chemical composition as follows: |  | | Journal (article/letter/editorial) | | gleichbleibendem Mn. Introduction Columbite-tantalite group minerals are ubiquitous in beryl-, complex-, albitespodumene-...(CÏerny et al., 1985). The columbite-tantalite group minerals are therefore important in deciphering...of columbite-tantalite group minerals from the Separation Rapids pegmatite group in N.W. Ontario ± a suite...Geological setting The Separation Rapids pegmatite group and the pluton with which it is associated lie almost...and mineralogy, the Separation Rapids pegmatite group is regarded as the easterly extension of the Winnipeg |  | | Book | | of this here. Next we must consider a peculiar group of Magnesium (Mg) has two more electrons than elements...appropriate and, indeed, these are linked with an (Si04) group in the mineral forsterite. The chemical short¬ hand...valencies and a bracket around the dis¬ tinctive (Si04) group would result in forsterite symbolized thus: (Mg2)4...ion O2- is divalent, the (P04)3- group is trivalent; the (Si04)4~ group in merwinite is tetravalent because...take the pure magnesium and iron members of the group of minerals known as olivines. These are called |  | | Journal (issue) | | Switzerland, U.S.A. ASSAYERS to the BANK OF ENGLAND Analytical Chemists, Samplers, etc. SPECIALITY:...British Guiana . Petroleum Developments Magnetite in West Indian Beach Sands Vermiculite Monograph, The...Geological Surveys . . . . . . . . . 190 Statistical Group Introduction to Geology. W. D. Keller . . 3rd...with porphyry and scattered over hillsides on the west bank of Dry River, in the Marsl1all's Hall area...bridle track for about two ip.iles to tl1e south-west. A new road for this latter distance would be necessary |
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