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Fransoletite, a new calcium beryllium phosphate from the Tip Top pegmatite, Custer, South Dakota
No full textFransoletite, is a new mineral from the Tip Top Pegmatite, Custer, South Dakota, with ideal composition H2Ca3Be2(PO4)4.4H2O. It occurs as aggregates of crystals up to 3 mm in diameter as a secondary mineral in association with beryl. Fransoletite is monoclinic, space group P21/a, with a = 7.354(7), b = 15.07(2), c = 7.055(7) Å and β = 96.41(8)°, Z = 2. It is colorless, hardness (Mohs) = 3, and has an imperfect {010} cleavage. It is optically biaxial, positive, with α = 1.560, β = 1.566, γ 1.586, 2V = 25°, Y = b, Z ⋀ c = 14°. The principal lines in the powder diffraction pattern are (d, I/Io, hkl) : 7.52, 40, 020 ; 3.47, 90, 131 ; 3.32, 70, 041, 21-1 ; 3.044, 100, 211, 12-2 ; 2.597, 40, 132 ; 2.317, 50, 250, 320. The name is in honor of Dr. André -Mathieu Fransolet, University of Liège, Belgium.La fransoletite est un nouveau minéral provenant de la pegmatite de Tip Top, Custer, South Dakota ; elle a pour composition chimique idéale H2Ca3Be2(PO4)4.4H2O. On la trouve sous forme d'agrégats de petits cristaux n'excédant pas 3 millimètres ; c'est un phosphate secondaire associé au béryl. La fransoletite est monoclinique, et a comme groupe spatial P21/a avec a = 7,354(7), b = 15,07(2), c = 7,055(7) Å et β = 96,41(8)°, Z = 2. La fransoletite est incolore, la dureté = 3, le clivage {010} est imparfait, biaxe (+), np = 1,560, nm = 1,566, ng = 1,586, 2V = 25°, Y = b, Z ⋀ c = 14°. Les raies les plus intenses du diagramme de poudre sont (d, l/lo, hkl) : 7,52, 40, 020 ; 3,47, 90, 131 ; 3,32, 70, 041, 21-1 ; 3,044, 100, 211, 12-2 ; 2,597, 40, 132 ; 2,317, 50, 250, 320.
Le nom est en l'honneur du Dr André-Mathieu Fransolet de l'Université de Liège, Belgique.Peacor Donald R., Dunn Pete J., Roberts Willard Lincoln, Campbell Thomas J., Newbury Dale E. Fransoletite, a new calcium beryllium phosphate from the Tip Top pegmatite, Custer, South Dakota. In: Bulletin de Minéralogie, volume 106, 5, 1983. pp. 499-503
L'huréaulite : ses propriétés minéralogiques et son rôle dans l'évolution génétique des phases Li (Fe, Mn) PO4
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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