Titlebook: Lanthanides, Tantalum and Niobium; Mineralogy, Geochemi Peter M?ller,Petr ?erny,Francis Saupé Conference proceedings 1989 Springer-Verlag B

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braggadocio

Mineralogy of the Rare-Earth Elements for feldspars used in porcelain manufacture. Johann Gadolin, former student of Torbern Bergman at the Uppsala University, analyzed this sample in 1794, finding a “new earth”. In 1797, Anders Gustaf Ekeberg again examined it and gave the name of “yttria” to the new element (in fact, a mixture of sev

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macular-edema

Pyrochlore Group Minerals from the Qaqarssuk Carbonatite Complexacent to late stage lanthanide-rich carbonatite, often together with apatite, magnetite and zircon. No PyGM are found in carbonatites of the main intrusive phase. This indicates that Nb and Ta have been concentrated in, and precipitated from, the residual fluids..Elements like Nb, Ta, U, Th and lant

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REE(Y), Nb, and Ta Enrichment in Pegmatites and Carbonatite-Alkalic Rock Complexesllow different fractionation trends. In alkalic rock-carbonatite complexes, however, REE(Y) and Nb(Ta) are always concentrated together. This geochemical coherence is remarkable because REE(Y) are expected to act as cations, whereas Ta and Nb form nuclei of complex anions. Both element suites are co

有權(quán)

Geochemistry of Granites Associated with Tantalum and Niobium Mineralization by the development of pervasive, postmagmatic alteration. Three major varieties of granite can be recognized:.Many granites associated with tantalum and niobium mineralization are zoned vertically, with the finer-grained porphyritic, granophyric, pegmatitic and/or miarolitic rocks which occur in sm

neologism

MOAT

藕床生厭倦

Geologic Characteristics and Genetic Problems Associated with the Development of Granite-Hosted Depoally specialized granite plutons. Such mineralization usually reaches a maximum in association with albite and fluorite (±lithium)-rich zones in small, late-stage intrusions. These zones are formed in some cases by crystallization of fluorine-rich magmas, and in other cases may result from postmagma