Spectroscopic study of inclusions in gem corundum from Mercaderes, Cauca, Colombia

Autor(en)

Manuela Zeug, Andrés Ignacio Rodríguez Vargas, Lutz Nasdala

Abstrakt

Mineral inclusions in gem corundum from Mercaderes, Cauca, Colombia, were investigated non-destructively using Raman and photoluminescence spectroscopy, with special focus lying on phases containing radioactive elements. Besides abundant rutile, the minerals zircon, apatite, feldspar, and an epidote-group species, most probably allanite–(Ce), were found. The latter is detected easily from its characteristic Nd

³⁺emission pattern, which may prove useful in future provenance studies. Zircon inclusions range from well crystalline to moderately radiation damaged [FWHM (full width at half band maximum) of the ν

₃(SiO

₄) Raman band 1.8–10.9 cm

⁻¹]. Both the zircon inclusions and their neighbouring host corundum are affected by compressive stress, which is assigned to (1) heterogeneous volume expansion of the host-inclusion couple upon pressure release during the uplift following primary growth and (2) volume expansion of the zircon inclusion due to the accumulation of self-irradiation damage. Internal stress of zircon inclusions averages ~1.1 GPa. Heat treatment of corundum leads to structural reconstitution of zircon (narrowed zircon Raman bands with FWHMs in the range 1.8–2.7 cm

⁻¹) and accompanying stress release in the adjacent corundum (indicated by downshifts of the R

₁emission of Cr

³⁺). The observation of broadened Raman band of zircon inclusions therefore allows one to exclude high-temperature enhancement of the host corundum.

Organisation(en)

Institut für Mineralogie und Kristallographie

Externe Organisation(en)

Minerlab Limitada, Bogota

Journal

Physics and Chemistry of Minerals

Band

44

Seiten

221-233

Anzahl der Seiten

13

ISSN

0342-1791

DOI

https://doi.org/10.1007/s00269-016-0851-4

Publikationsdatum

10-2016

Peer-reviewed

Ja

ÖFOS 2012

104026 Spektroskopie, 105116 Mineralogie

Schlagwörter

ASJC Scopus Sachgebiete

Geochemistry and Petrology, Allgemeine Materialwissenschaften

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/2e1ea09d-b7e5-4979-ba5c-d8ca68315790