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On the constitution of the alkali feldspars
Tschermaks Mineralogische und Petrographische Mitteilungen, 1965The crystalline variants of the alkali feldspars differ from each other in the pattern of Al/Si disorder. The interrelations of the several variants are graphically shown in Figs. 1, 2, and 3. In high albite thekind of disorder is different from that in any other alkali feldspar; therefore the transition high albite→monalbite is diffusive; but the ...
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Nature, 1966
IT has long been assumed that the degree of ordering between silicon and aluminium in the tetrahedral sites of feldspars is related to the conditions of formation of the minerals. A direct test of this idea has, up to the present, been hampered by the lack of an easy method of measuring the degree of order in a genetically related suite of feldspars ...
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IT has long been assumed that the degree of ordering between silicon and aluminium in the tetrahedral sites of feldspars is related to the conditions of formation of the minerals. A direct test of this idea has, up to the present, been hampered by the lack of an easy method of measuring the degree of order in a genetically related suite of feldspars ...
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Alkali interdiffusion in alkali feldspars
2014Cation exchange experiments were conducted at 800°C to 1000°C and 1 bar using oriented plates of sanidine and NaCl-KCl salt mixtures as starting material. The formation of interdiffusion fronts propagating into the sanidine by Na-K-interdiffusion on the alkali sublattice was observed.
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Twin microstructures in alkali feldspars
2021This thesis was scanned from the print manuscript for digital preservation and is copyright the author. Researchers can access this thesis by asking their local university, institution or public library to make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
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Alkali-feldspars: Which solvus?
Physics and Chemistry of Minerals, 1978Variation in published alkali-feldspar solvus curves is discussed in the light of the concept of complete (crystal-crystal) and exchange (crystal-fluid-crystal) equilibrium. Exchange equilibrium may lead to very regular solvus-like two-phase curves differing substantially from the true binodal solvus; certain experimental strategies tend to favour the ...
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Determining the coherent solvus for alkali feldspar
2022<p><span>Alkali feldspar is one of the most common rock forming minerals in magmatic and metamorphic rocks. It forms a solid-solution between the sodium and potassium end members. At temperatures above about 600</span><span>&#176;</span><span>C alkali feldspar ...
David Heuser +6 more
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Nepheline-alkali feldspar parageneses
American Journal of Science, 1954Cites and discusses analyses of nepheline and associated alkali feldspars from nepheline syenites and chemically equivalent rocks which demonstrate that the composition of the nepheline phase is related not only to the chemical environment but also to temperature of crystallization (or recrystallization) of the host rock.
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Stability of the IRSL Spectra of Alkali Feldspars
physica status solidi (b), 1997Measurements of infrared stimulated luminescence (IRSL) emission spectra are presented for detrital potassium-rich feldspars separated from sands and for museum specimens of low albite and intermediate microcline. The samples show common emission bands at 335, 400 and 550 nm and a thermally unstable emission band at 290 nm which is associated with ...
M.L. Clarke, H.M. Rendell
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Pulsed photostimulated luminescence of alkali feldspars
Radiation Measurements, 1994Abstract The use of pulsed photostimulation techniques has a number of practical and conceptual attractions compared with continuous stimulation approaches. Enhanced signal-to-background ratios, opportunities for signal recovery techniques, and ability of detecting luminescence asynchronously and close to stimulation wavelengths are all of practical ...
D.C.W. Sanderson, R.J. Clark
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Titanium as a cathodoluminescence activator in alkali feldspars
American Mineralogist, 2008Albite patches in coarsely mesoperthitic alkali feldspars from the Klokken syenite have oscillatory zoning seen at blue wavelengths using cathodoluminescence. Using a five-spectrometer, high-resolution elemental mapping technique in an electron probe, we show a close correspondence between CL emission intensity and Ti, present at levels up to ∼200 ppm.
Parsons, Ian +3 more
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