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Vesuvian

Selenium was first identified by Berzelius in 1817. The element is found associated with volcanic activity, as for example in cavities of Vesuvian lavas and in the volcanic tuff of Wyoming (about 150 parts per million). [Pg.1464]

Tetragonal Two equal axes and one longer, all at right angles to each other Prism, pyramid Vesuvian, rutile, chalcopyrite... [Pg.5]

Sorosilicates are minerals in which two Si04 tetrahedra combine to produce Si2C>7. Many members of this group are complex compounds that contain several elements, the (OH) molecule and water, as well as the silicate radical. Most species in this group are rare. The gem minerals tanzanite, a variety of zoisite, and vesuvian (idocrase) fall within this group. [Pg.20]

Vesuvian (Idocrase) Complex calcium aluminum silicate Opaque to translucent green or brown (a.k.a. Happy Camp jade ) 1.49-1.69 3 2.7... [Pg.39]

Jade is the common name for gem-quality specimens of two distinctly different mineral species, jadeite and the massive variety of actinolite, called nephrite. The word jade is derived from the Spanish piedra deyjada, meaning stone of the flank. This refers to its popular use as a cure for diseases of the kidneys and liver. Other minerals that have been mistaken for jade, or used as jade imitations include green jasper (quartz), vesuvian (idocrase), massive grossular garnet, chloromelanite (a mixture of dark pyroxenes) (Table 2.10). [Pg.39]

Lithium has been detected by the spectroscope in many other minerals. It is found in mineral waters, in the ashes of plants such as cocoa, tobacco, sugar-cane, and sea-weed, and traces of its sulphate have been detected in the salts of the Vesuvian fumaroles.1 Its presence in the sun s atmosphere was established by Lockyer.2... [Pg.52]

After the observations of Boetius de Boot "sexangula figura" and Rome de I lsle "mica lamellaux hexagone" Haiy (1801), on the basis of m easurements on a crystal from Vesuvius, described mica as orthorhombic with a prism angle of 60°. He concluded this even after Boumon in 1817 correctly assigned mica to the monoclinic system. Later measurements by Phillips (1837), again on Vesuvian specimens, confirmed the monoclinic symmetry. [Pg.485]

The accuracy of data for fluorine obtained by EMPA, SIMS, and SREF in humite group minerals was discussed by Ottolini et al. [63], Discrepancies of fluorine data between EMPA (standard fluorite F-A a,TAP no APF corrections) and SIMS were detected in vesuvian-ites and micas [64,65]. The former are systematically lower than the latter. Additional X-ray refinement on some crystals of the set gave a better agreement between the SIMS data and calculated site-scattering at Oil (A Oil [%] in the range 0.0-1.4 [%]),where the refinement shows F to be preferentially ordered. This observation seems to provide support, on one hand, to the accuracy of SIMS, and on the other, it confirms the need of extensive study and test (in particular, about the choice of the calibration standards) in the analysis for F by electron microprobe in such complex matrices. [Pg.1026]

Fig. 1 ( " Th/ " Th)versus " Thplot for whole-rock and mineral separate zero-age samples from Vesuvius. From Capaldi and co-workers. 1944 refers to mineral separates from the lava erupted in 1944 other numbers are laboratory numbers of cumulate ejecta. Most cumulates have large ("" Ra/"" U) ratios so their age is zero in comparison with half-life of " Th. Hyperbolic correlation strongly suggests that Th in Vesuvian lavas is derived by mixing of two components with different Th isotopic compositions (i.e. derived from two sources with different Th/ " U ratios). Because data include whole-rock lavas and different minerals drawn hyperbola is not believed to be mixing curve of magmas... Fig. 1 ( " Th/ " Th)versus " Thplot for whole-rock and mineral separate zero-age samples from Vesuvius. From Capaldi and co-workers. 1944 refers to mineral separates from the lava erupted in 1944 other numbers are laboratory numbers of cumulate ejecta. Most cumulates have large ("" Ra/"" U) ratios so their age is zero in comparison with half-life of " Th. Hyperbolic correlation strongly suggests that Th in Vesuvian lavas is derived by mixing of two components with different Th isotopic compositions (i.e. derived from two sources with different Th/ " U ratios). Because data include whole-rock lavas and different minerals drawn hyperbola is not believed to be mixing curve of magmas...
The data in Fig. 3, therefore, can be replotted as a function of the oxidation percentage of U (Fig. 4). Vesuvius is a remarkable exception to the trends in Figs. 3 and 4 perhaps the transport of U and Th at Vesuvius is controlled prevalently by halogens, which are present in very large amounts in Vesuvian lavas. Data from Faial and Tristan (not plotted in Figs. 3 and 4) show ( Th/ U) ratios higher than unity, and confirm that rocks from oceanic environments were prevalently enriched in Th rather than U. [Pg.8]

Decarboxythamnolic acid Methyl virensate Vesuvianic acid... [Pg.15]

Ingolfsdottir K, Hylands PJ, Solberg Y (1986) Structure of vesuvianic acid from Stereocaulon species. Phytochemistry 25 550-553... [Pg.462]

Substictic acid Vesuvianic acid see 357 >270, dec. Aspicilia mashiginensis... [Pg.131]

Vesuvianic acid (81) Isidiophorin (82) Rhizonyl alcohol (83) Rhizonyl aldehyde (84) Pulmonarianin (85) Diffractaic acid (86) Ergosterol peroxide (87)... [Pg.254]

See other pages where Vesuvian is mentioned: [Pg.459]    [Pg.425]    [Pg.657]    [Pg.9]    [Pg.17]    [Pg.111]    [Pg.425]    [Pg.657]    [Pg.590]    [Pg.590]    [Pg.312]    [Pg.42]    [Pg.864]    [Pg.510]    [Pg.563]    [Pg.5]    [Pg.5]    [Pg.39]    [Pg.120]    [Pg.351]    [Pg.534]    [Pg.129]    [Pg.252]   


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Vesuvianic acid

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