Sökning: onr:"swepub:oai:DiVA.org:nrm-4194" >
Mn-bearing purplish...
Mn-bearing purplish-red tourmaline from the Anjanabonoina pegmatite, Madagascar
-
- Bosi, Ferdinando (författare)
- Sapienza Università di Roma, Italy
-
- Celata, Beatrice (författare)
- Sapienza Università di Roma, Italy
-
- Skogby, Henrik (författare)
- Naturhistoriska riksmuseet,Enheten för geovetenskap
-
visa fler...
-
- Hålenius, Ulf (författare)
- Naturhistoriska riksmuseet,Enheten för geovetenskap
-
- Tempesta, Gioacchino (författare)
- University of Bari "Aldo Moro", Italy
-
- Ciriotti, Marco (författare)
- University of Turin, Italy
-
- Bittarello, Erica (författare)
- Univerity of Turin, Italy
-
- Marengo, Alessandra (författare)
- Univerity of Turin, Italy
-
visa färre...
-
(creator_code:org_t)
- 2021-03-01
- 2021
- Engelska.
-
Ingår i: Mineralogical magazine. - : Mineralogical Society. - 0026-461X .- 1471-8022. ; 85:2, s. 242-253
- Relaterad länk:
-
https://nrm.diva-por... (primary) (Raw object)
-
visa fler...
-
https://www.cambridg...
-
https://urn.kb.se/re...
-
https://doi.org/10.1...
-
visa färre...
Abstract
Ämnesord
Stäng
- A gem-quality purplish-red tourmaline sample of alleged liddicoatitic composition from the Anjanabonoina pegmatite, Madagascar, hasbeen fully characterised using a multi-analytical approach to define its crystal-chemical identity. Single-crystal X-ray diffraction, chem-ical and spectroscopic analysis resulted in the formula: X(Na0.41□0.35Ca0.24)Σ1.00Y(Al1.81Li1.00Fe3+0.04Mn3+0.02Mn2+0.12Ti0.004)Σ3.00ZAl6[T(Si5.60B0.40)Σ6.00O18](BO3)3(OH)3W[(OH)0.50F0.13O0.37]Σ1.00, which corresponds to the tourmaline species elbaite having the typical space group R3m and relatively small unit-cell dimensions, a= 15.7935(4) Å, c= 7.0860(2) Å and V= 7.0860(2) Å3.Optical absorption spectroscopy showed that the purplish-red colour is caused by minor amounts of Mn3+(Mn2O3= 0.20 wt.%).Thermal treatment in air up to 750°C strongly intensified the colour of the sample due to the oxidation of all Mn2+ to Mn3+ (Mn2O3 up to 1.21 wt.%). Based on infrared and Raman data, a crystal-chemical model regarding the electrostatic interaction betweenthe X cation and W anion, and involving the Y cations as well, is proposed to explain the absence or rarity of the mineral species ‘liddicoatite’.
Ämnesord
- NATURVETENSKAP -- Geovetenskap och miljövetenskap -- Geokemi (hsv//swe)
- NATURAL SCIENCES -- Earth and Related Environmental Sciences -- Geochemistry (hsv//eng)
Nyckelord
- The changing Earth
- Den föränderliga jorden
Publikations- och innehållstyp
- ref (ämneskategori)
- art (ämneskategori)
Hitta via bibliotek
Till lärosätets databas