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Journal Article
Published: 01 March 2000
European Journal of Mineralogy (2000) 12 (2): 273-291.
...Stefan MELZER; Matthias GOTTSCHALK; Michael ANDRUT; Wilhelm HEINRICH Abstract Solid solutions in the ternary K-richterite-richterite-tremolite (K x Na y □ 1-x-y )(Na x+y Ca 2-x-y ) 2 Mg 5 [Si 8 O 22 /(OH) 2 ] have been synthesized at 200 MPa and 800°C using cold-seal vessels, and at 1800 MPa...
FIGURES | View All (9)
Journal Article
Published: 24 April 2008
Geological Magazine (2008) 145 (4): 570-585.
... magma produced different emplacement forms such as dome/plug-shaped bodies and lava flows, showing variation in volume and texture. The mineralogical constituents of the lamproites are sanidine, olivine (77 < Mg no. < 81), phlogopite (74 < Mg no. < 78), K-richterite, clinopyroxene (74 <...
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Journal Article
Published: 01 February 1986
American Mineralogist (1986) 71 (1-2): 17-37.
... elements are regularly partitioned between co-crystallizing phases: e.g., Fe, Mg and Ti between richterite and phlogopite; Na and K between feldspar and richterite; tetrahedral deficiency between phlogopite and richterite. These observations lead to the conclusion that the peralkaline character...
Journal Article
Published: 01 October 1983
American Mineralogist (1983) 68 (9-10): 924-943.
...Maryellen Cameron; Shigeho Sueno; J. J. Papike; C. T. Prewitt Abstract Crystal structure parameters have been determined for synthetic potassium richterite K(NaCa)Mg 5 Si g O 22 F 2 at 24°, 400°, 600°, and 800°C, and synthetic sodium richterite Na(NaCa) Mg 5 Si 8 O 22 F 2 at 24°, 400°, 600°, 800...
Journal Article
Published: 01 February 2004
Mineralogical Magazine (2004) 68 (1): 83-100.
...E. Salvioli-Mariani; L. Toscani; D. Bersani Abstract The lamproite of Gaussberg is an ultrapotassic rock where leucite, olivine and clinopyroxene microphenocrysts occur in a glass-rich groundmass, containing microliths of leucite, clinopyroxene, apatite, phlogopite and rare K-richterite. Abundant...
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The stability field of pure KNaCaMg 5 Si 8 O 22 (OH) 2  <b>K</b>-<b>richterite</b> as bra...
Published: 01 January 2006
Figure 11. The stability field of pure KNaCaMg 5 Si 8 O 22 (OH) 2 K-richterite as bracketed by Trønnes (2002) is shown by curve (A). All of the indicated named products are with respect to curve (A) with Wad being wadite-structured K 2 Si 4 O 9 , X is Phase X, en and Cen are enstatite
Comparison of cation coordinations in  C 2&#x2F; c  omphacite, <b>K</b>-<b>richterite</b>, and...
Published: 01 October 2001
F igure 2. Comparison of cation coordinations in C 2/ c omphacite, K-richterite, and (21)- clinopyribole. Note the similarity between the MS2 site in (21)-clinopyribole and the M4 site in K-richterite, and that between the MD4 site in (21)-clinopyribole and the M2 site in C 2/ c omphacite.
Journal Article
Published: 01 December 1986
American Mineralogist (1986) 71 (11-12): 1426-1433.
...Annibale Mottana; William L. Griffin Abstract Two coexisting F-bearing K-richterites from the blueschist-facies metamorphic manganese ore deposit St. Marcel (Val d’Aosta, Italy) have been studied by combined empa and ir analytical techniques. Despite their different colors (pink and blue) and cell...
Published: 01 January 2013
EISBN: 9780903056434
... yellow and brownish absorption colours. It is distinguished from aenigmatite by its less intense absorption colours and lower refractive indices. Most richterites occur in metamorphic rocks, e.g. contact metamorphosed limestones, and in skarns. K-rich magnesiorichterite, which has an extensive...
Journal Article
Published: 01 April 1999
American Mineralogist (1999) 84 (4): 681-684.
...Hexiong Yang; Juergen Konzett; Charles T. Prewitt; Yingwei Fei Abstract The crystal structure of a potassic richterite, K(KCa)Mg 5 Si 8 O 22 (OH) 2 synthesized at 15 GPa and 1400 degrees C, was refined from single-crystal X-ray diffraction data. The unit-cell parameters are: a = 10.1926(5), b...
Journal Article
Published: 01 August 2008
Mineralogical Magazine (2008) 72 (4): 877-886.
...M. D. Welch; J. J. Reece; S. A. T. Redfern Abstract The distribution of Mg and Ni over the octahedrally-coordinated sites M (1,2,3) in Ni-substituted potassic richterite solid solution, A K B (NaCa) C (Mg 2.5 Ni 2.5 )Si 8 O 22 (OH) 2 , synthesized at 0.1 GPa/750°C (25 days), has been studied...
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Journal Article
Published: 01 February 1995
American Mineralogist (1995) 80 (1-2): 162-164.
..., which are richer in OH, Ti, Fe, Na, and K. Similar sodic-calcic amphiboles are widely known to appear in lamproites, but typically they contain 5% or more K 2 O, whereas the present sample reaches a maximum of 1.18% K 2 O at the margin. As is characteristic of titanian potassium richterite, there is Ti...
Journal Article
Published: 01 October 1993
American Mineralogist (1993) 78 (9-10): 980-987.
...Giancarlo Della Ventura; Jean-Louis Robert; Jean-Michel Beny; Mati Raudsepp; Frank C. Hawthorne Abstract Amphiboles were synthesized along the join K(NaCa)Mg 5 (Si 7.4 Ti 0.6 )O 22 (OH,F) 2 from (OH) = 2 to F = 2 apfu (atoms per formula unit). Rietveld structure refinement shows that Ti 4...
Journal Article
Published: 01 December 1970
American Mineralogist (1970) 55 (11-12): 1973-1992.
... relationship between end member compositions; b and c change little with composition. The molar volume decreases 3.55 cm 3 /mole in passing from potassic to sodic richterite compositions; other K⇌Na ( A -site) amphibole series are expected to show a similar molar volume change. High pressures characteristic...
Journal Article
Published: 01 June 1983
American Mineralogist (1983) 68 (5-6): 494-505.
.... Associated characteristic minerals are K-richterite, phlogopite, Nb-Cr-rutile and Nb-Cr-Mg-ilmenite, together with olivine, orthopyroxene, Cr-diopside, and Mg-Cr-spinel. Garnet is typically absent. The new minerals formed by metasomatizing fluids enriched in K + Ba + REE + Ti that infiltrated source rocks...
Journal Article
Published: 01 March 2001
Bulletin de la Société Géologique de France (2001) 172 (2): 189-200.
... to the calc-alkaline Black Dyke lavas, and is mainly juvenile judging from Nd isotopic ratios. The source may correspond either to a juvenile crust composed of high-K andesites [Roberts and Clemens, 1993], which could be the Black Dyke lavas, or to phlogopite-K-richterite enriched lithospheric mantle. In both...
Journal Article
Published: 01 June 2009
Mineralogical Magazine (2009) 73 (3): 457-477.
... and tetraferriphlogopite, groundmass potassic amphiboles, Sr-rich apatite and monazite-(Ce), late stage Na-poor K-feldspar and quartz. The rocks differ in terms of the character of the amphiboles (Ti-potassian arfvedsonite vs . K-richterite-K-magnesioarfvedsonite-K-arfvedsonite solid solution), spinel compositions...
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Journal Article
Published: 01 December 1998
American Mineralogist (1998) 83 (11-12_Part_1): 1323-1329.
... platelets, typically 30-70 mu m maximum dimension, which often show hexagonal morphology. Associated minerals are diopside, olivine, phlogopite, Ti-K-richterite, chrome spinel, ilmenite, priderite, and jeppeite. Haggertyite has a magnetoplumbite-type structure. Typical microprobe analyses give (as wt...
Journal Article
Published: 01 August 1997
Canadian Journal of Earth Sciences (1997) 34 (8): 1118-1127.
... and bulk-rock compositions typical of phlogopite lamproite (i.e., Ti-rich and Al-poor phlogopite, K-richterite, 4 < K 2 O/Na 2 O < 5, and very high contents of incompatible elements (Ba, Sr, light rare earth elements)). Moreover, these dikes show textural, mineralogical, and bulk-rock features...
Journal Article
Published: 01 February 1990
American Mineralogist (1990) 75 (1-2): 97-104.
... peridotite group. These include the paucity of phlogopite and absence of K-richterite in the former, precluding a simple genetic relationship between the two groups. Copyright © 1990 by the Mineralogical Society of America 1990 ...