Precious and Decorative Stones

2019: No. 1 (95) CONTENTS

DOI: https://doi.org/10.53056/...

Complex gemological studies of alexandrite with atypical diagnostic features

Yu. Gayevsky
State Gemmological Centre of Ukraine

Yu. Ladzhun
State Gemmological Centre of Ukraine

О.Belichenko
State Gemmological Centre of Ukraine

Language: Ukrainian

Precious and Decorative Stones. No. 1 (95), 2019: 4–6

Abstract
The results of complex gemological studies of alexandrite with atypical diagnostic features are presented. The main gemological characteristics were specified, a microscopic study of internal inclusions was carried out as well as qualitative X-ray fluorescence analysis (EXDRF) and IR Fourier spectroscopy studies were performed. According to the authors, revealed significant increase in the refractive index and birefringence of the sample along with the absence of fluorescence are due to the presence of an increased iron amount in the stone.

Keywords: alexandrite, complex gemological studies, microscopy, X-ray fluorescence analysis, IR Fourier spectroscopy.

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