THE Ta-Nb-Sn-Ti OXIDE-MINERAL PARAGENESIS FROM LA VIQUITA, A SPODUMENE-BEARING RARE-ELEMENT GRANITIC PEGMATITE, SAN LUIS, ARGENTINA

2008 ◽  
Vol 46 (2) ◽  
pp. 379-393 ◽  
Author(s):  
M. A. Galliski ◽  
M. F. Marquez-Zavalia ◽  
P. Cerny ◽  
V. A. Martinez ◽  
R. Chapman
Keyword(s):  
Granitic Pegmatite ◽  
Rare Element ◽  
Mineral Paragenesis ◽  
Oxide Mineral ◽  
San Luis

A Ta,Ti–rich oxide mineral assemblage from the Nancy beryl–columbite–phosphate granitic pegmatite, San Luis, Argentina

2019 ◽  
Vol 113 (5) ◽  
pp. 687-701
Author(s):  
Miguel Ángel Galliski ◽  
María Florencia Márquez-Zavalía ◽  
Radek Škoda ◽  
Milan Novák ◽  
Renata Čopjaková ◽  
...  
Keyword(s):  
Mineral Assemblage ◽  
Granitic Pegmatite ◽  
Oxide Mineral ◽  
San Luis

scholarly journals Nb–Ta–(Ti–Sn) oxide mineral chemistry as tracer of rare-element granitic pegmatite fractionation in the Borborema Province, Northeastern Brazil

2007 ◽  
Vol 43 (2) ◽  
pp. 207-228 ◽  
Author(s):  
Hartmut Beurlen ◽  
Marcelo R. R. Da Silva ◽  
Rainer Thomas ◽  
Dwight R. Soares ◽  
Patrick Olivier
Keyword(s):  
Mineral Chemistry ◽  
Northeastern Brazil ◽  
Granitic Pegmatite ◽  
Rare Element ◽  
Oxide Mineral ◽  
Borborema Province

The Phosphate Mineral Assemblages from La Viquita Pegmatite, San Luis, Argentina

2021 ◽  
Author(s):  
Miguel A. Galliski ◽  
Encarnación Roda-Robles ◽  
Frédéric Hatert ◽  
María Florencia Márquez-Zavalía ◽  
Viviana A. Martínez
Keyword(s):  
Late Stage ◽  
Secondary Growth ◽  
Mineral Association ◽  
Rare Element ◽  
Mineral Paragenesis ◽  
San Luis ◽  
Phosphate Mineral ◽  
Mineral Assemblages ◽  
Apatite Group

Abstract La Viquita is a rare-element pegmatite of LCT signature, REL-Li subclass, spodumene subtype, that shows Fe > Mn mineral paragenesis instead of Mn > Fe, which is more common in the rare-element pegmatite population of the San Luis ranges. The phosphate mineral association of this pegmatite can be subdivided into (1) primary, with dendritic triphylite [(Fe/(Fe + Mn) = 0.72] and montebrasite–amblygonite as main phases; (2) metasomatic, with subsolidus replacement of triphylite by ferrisicklerite and heterosite; and (3) hydrothermal, with secondary growth of alluaudite at the expense of heterosite and wardite from montebrasite caused by Na-metasomatism. A Ca-rich influx under oxidizing conditions produced childrenite–eosphorite–ernstite, jahnsite-(CaMnFe), and kingsmountite. Apatite-group minerals are present throughout the processes. Very late-stage solutions formed millimetric crystals of hydroxylherderite associated with hydroxylapatite in cavities in K-feldspar.

Phosphate nodules containing two distinct assemblages in the Cema granitic pegmatite, San Luis province, Argentina: Paragenesis, composition and significance

2012 ◽  
Vol 50 (4) ◽  
pp. 913-931 ◽  
Author(s):  
E. Roda-Robles ◽  
M. A. Galliski ◽  
M. B. Roquet ◽  
F. Hatert ◽  
P. de Paeseval
Keyword(s):  
Granitic Pegmatite ◽  
San Luis

The Zebra Granitic Pegmatite, San Luis, Argentina

2020 ◽  
Author(s):  
Miguel Ángel Galliski ◽  
Robert F. Martin ◽  
María Florencia Márquez-Zavalía
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Intermediate Zone ◽  
Granitic Pegmatite ◽  
Random Orientation ◽  
Type Host ◽  
San Luis ◽  
Quartz Grains ◽  
Optical Continuity ◽  
The Rare Earth

Abstract We describe an unusual example of rhythmically layered peraluminous granitic pegmatite locally developed in the intragranitic Potrerillos NYF pegmatites derived from the A-type host granites of the Las Chacras–Potrerillos batholith, Sierra de San Luis, Argentina. The strikingly rhythmic layers in the Zebra pegmatite consist of units of albite–K-feldspar–quartz–K-feldspar–albite, with accessory tourmaline and minor muscovite. The layers crystallized from a boron-bearing melt ponded and thermally insulated in the intermediate zone. A layer of low albite 1–2 cm thick was followed by coarser-grained K-feldspar, then well-ordered microcline, which gives way to quartz grains, also coarser-grained, in optical continuity. Zoned prismatic crystals of schorl nucleated in the feldspathic layer in random orientation. Muscovite is scarce. The rock has a granitic composition enriched in Rb, Cs, and B, and is depleted in the rare-earth elements compared to its precursor. We contend that the normative composition, 35.3% Or, 38.1% Ab, and 21.3% Q, was close to the eutectic in the granite system modified by dissolved H2O, F, and B, at a P(H2O) close to 3.5 kbar and a temperature in the range 575–600 °C. Repeated incursions from the field of Ab + Or to the field of quartz and back again as the melt was producing bubbles of H2O can account for the rhythmic crystallization and the local truncation or merging of the feldspathic layers. Occasional larger crystals of K-feldspar may have become detached from the wall or roof of the chamber.

scholarly journals Rare-element granitic pegmatite of Miocene age emplaced in UHP rocks from Visole, Pohorje Mountains (Eastern Alps, Slovenia): accessory minerals, monazite and uraninite chemical dating

2014 ◽  
Vol 65 (2) ◽  
pp. 131-146 ◽  
Author(s):  
Pavel Uher ◽  
Marian Janák ◽  
Patrik Konečný ◽  
Mirijam Vrabec
Keyword(s):  
Late Miocene ◽  
Volcanic Rocks ◽  
Eastern Alps ◽  
Granitic Pegmatite ◽  
Fault System ◽  
Rare Element ◽  
Accessory Minerals ◽  
Precipitation Temperature ◽  
The Alps ◽  
Chemical Dating

Abstract The granitic pegmatite dike intruded the Cretaceous UHP rocks at Visole, near Slovenska Bistrica, in the Pohorje Mountains (Slovenia). The rock consists mainly of K-feldspar, albite and quartz, subordinate muscovite and biotite, while the accessory minerals include spessartine-almandine, zircon, ferrocolumbite, fluorapatite, monazite- (Ce), uraninite, and magnetite. Compositions of garnet (Sps48-49Alm45-46Grs + And3-4 Prp1.5-2), metamict zircon with 3.5 to 7.8 wt. % HfO2 [atom. 100Hf/(Hf + Zr) = 3.3-7.7] and ferrocolumbite [atom. Mn/(Mn + Fe) = 0.27-0.43, Ta/(Ta + Nb) = 0.03-0.46] indicate a relatively low to medium degree of magmatic fractionation, characteristic of the muscovite - rare-element class or beryl-columbite subtype of the rare-element class pegmatites. Monazite-(Ce) reveals elevated Th and U contents (≤11 wt. % ThO2, ≤5 wt. % UO2). The monazite-garnet geothermometer shows a possible precipitation temperature of ~495 ± 30 °C at P~4 to 5 kbar. Chemical U-Th-Pb dating of the monazite yielded a Miocene age (17.2 ± 1.8 Ma), whereas uraninite gave a younger (~14 Ma) age. These ages are comtemporaneous with the main crystallization and emplacement of the Pohorje pluton and adjacent volcanic rocks (20 to 15 Ma), providing the first documented evidence of Neogene granitic pegmatites in the Eastern Alps. Consequently, the Visole pegmatite belongs to the youngest rare-element granitic pegmatite populations in Europe, together with the Paleogene pegmatite occurrences along the Periadriatic (Insubric) Fault System in the Alps and in the Rhodope Massif, as well as the Late Miocene to Pliocene pegmatites in the Tuscany magmatic province (mainly on the Island of Elba).

Metallogenesis of the Totoral LCT rare-element pegmatite district, San Luis, Argentina: A review

2019 ◽  
Vol 90 ◽  
pp. 423-439 ◽  
Author(s):  
Miguel Ángel Galliski ◽  
María Florencia Márquez-Zavalía ◽  
Diego Sebastián Pagano
Keyword(s):  
Rare Element ◽  
San Luis
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