Showing papers on "Silicate minerals published in 1974"
TL;DR: In this article, a Miocene shale section collected from an oil well drilled in coastal Louisiana were separated into fractions and analyzed for Sr 87 /Sr 86, Rb and Sr. 86.
47 citations
Patent•
10 Sep 1974
TL;DR: A method for removing bitumen from mineral particles recovered from bituminous froth recovered as a product of aqueous extraction of tar sands which method comprises scrubbing the minerals with a liquid hydrocarbon solvent containing at least 10 weight percent aromatics and thereafter separating the minerals from the solvent and subsequently drying the minerals as discussed by the authors.
Abstract: A method for removing bitumen from mineral particles recovered from bituminous froth recovered as a product of aqueous extraction of tar sands which method comprises scrubbing the minerals with a liquid hydrocarbon solvent containing at least 10 weight percent aromatics and thereafter separating the minerals from the solvent and subsequently drying the minerals.
21 citations
TL;DR: In this article, the distribution of phases in the naturally occurring silicate minerals hornblende and grunerite was studied using high-voltage electron microscopy and it was shown that there is a miscibility gap between them involving the segregation of calcium.
Abstract: Transmission, analytical and high-voltage electron microscopy have been used to study the distribution of phases in the naturally occurring silicate minerals hornblende and grunerite. These two minerals belong to the amphibole group and previous analytical work has suggested the existence of a miscibility gap between them involving the segregation of calcium. The minerals in the specimens studied are coarse-grained, having crystallized slowly during metamorphism.
16 citations
TL;DR: In this paper, two sample decomposition procedures are described for determining silicon in typical sulphide and silicate minerals and their mixtures, in ores, and in slags.
13 citations
01 Jan 1974
TL;DR: In this paper, a comparison of the data on these samples with data on terrestrial olivines and pyroxenes shows that the electrical conductivity of anhydrous silicate minerals is influenced primarily by the concentration, oxidation state, and distribution of iron, while the silicate crystal structure is only of secondary importance.
Abstract: Results are reported for laboratory measurements of the dc and low-frequency ac electrical conductivity of three lunar rocks with ferrous iron contents of 5 to 26 wt %. The measurements were made at temperatures ranging from 20 to 1000 C, and Mossbauer spectroscopy was used to determine the dependence of electrical conductivity on furnace atmosphere. It is found that the magnitude of electrical conductivity generally increases with increasing iron content. A comparison of the data on these samples with data on terrestrial olivines and pyroxenes shows that the electrical conductivity of anhydrous silicate minerals is influenced primarily by the concentration, oxidation state, and distribution of iron, while the silicate crystal structure is only of secondary importance. Lunar interior temperatures are deduced from experimental lunar conductivity profiles, and the resulting temperature-depth profiles are found to be consistent with those calculated for two different lunar evolutionary models as well as with various experimental constraints.
13 citations
TL;DR: In this article, the feasibility and the mechanism of the separation of pyrochlore from associated main silicate gangue minerals such as albite and biotite in an anionic collector system, using oleic acid and sodium dodecyl sulphate as collectors, in absence and presence of Fe(III), Cu(II), and Ca(II) have been investigated.
Abstract: The feasibility and the mechanism of the separation of pyrochlore from associated main silicate gangue minerals such as albite and biotite in an anionic collector system, using oleic acid and sodium dodecyl sulphate as collectors, in absence and presence of Fe(III), Cu(II) and Ca(II) have been investigated. Contrary to published data, the presence or addition of salts of these cations impairs rather than improves the selectivity of both soap and alkyl sulphate flotation of pyrochlore. However, leaching of the minerals investigated by HC1 greatly promotes their selective separation owing to selective teaching of metallic sites, namely Al3+, Mg2+ and Fe2+, from crystalline lattice surfaces of silicate minerals leading to the predominance of the negatively charged silicate sites. This leads to a marked sluggishness of their adsorbability of collector anions and their floatability. In contrast, leaching has almost no effect on the adsorptive capacity and floatability of pyrochlore due to the close chemical similarity of its cationic sites. Sodium dodecyl sulphate is superior to oleic acid because of its low pKa and the predominance of its collecting anions at pH of 2. These anions possess a great affinity for the positively charged Cb and Ta sites over negatively charged silicate sites, leading to the selective flotation of pyrochlore.
11 citations
Patent•
04 Oct 1974
TL;DR: In this paper, the authors present a calcining agglomerates consisting of particles of hydrous magnesium containing silicate minerals bonded together by means of feldspar minerals in a manner to form products characterized by their low specific gravity and low liquid absorbing properties.
Abstract: Fillers and extenders for use in coatings, paints, plastics, adhesives, sealants and the like are produced by calcining agglomerates consisting primarily of particles of hydrous magnesium containing silicate minerals bonded together by means of feldspar minerals in a manner to form products characterized by their low specific gravity and low liquid absorbing properties by reason of the presence of voids within the agglomerates while presenting a limited outer surface exposed for contact with liquids.
6 citations
4 citations
TL;DR: In this paper, it was shown that the crystal structures of the two phases are normally sufficiently similar that the transformation can occur by the spinodal mechanism, and that the exceedingly slow cooling rates at high temperatures experienced by many geologically important igneous minerals, result in a low density of favorable nucleation sites (grain boundaries and intragranular dislocation structures).
4 citations
TL;DR: Flame emission and atomic absorption procedures for determination of aluminum in typical sulphide and silicate minerals and in representative ores and slags are described in this paper, where the most satisfactory of three dissolution procedures used.
3 citations
25 Mar 1974
TL;DR: Optical U-stage measurements, chemical microprobe data, and X-ray procession photographs of a bytownite twin group from rock 12032,44 are compared in this paper.
Abstract: Optical U-stage measurements, chemical microprobe data, and X-ray procession photographs of a bytownite twin group from rock 12032,44 are compared. Sharp but weak b and no c-reflections were observed for this An89 bytownite indicating a partly disordered structure. Euler angles, used to characterize the orientation of the optical indicatrix, compare better with values for plutonic than for volcanic plagioclase. This indicates that structural and optical properties cannot be directly correlated.