Optical Properties and Natural Radioactivity Levels of Turkish Natural Glass Obsidian

Abstract

Obsidian is a naturally occurring volcanic glass formed as an igneous rock. It is a kind of alumino-silicate glass containing iron impurities and some tiny particles (particle-dispersed glasses). It can be found in black, gray, brown, blue, and green colors in nature. In recent work, the obsidian specimens in black and brown colors were collected from Sarıkamış which is a small town in Kars province located at the north-east part of Turkey. The obtained specimens were then cut and polished to obtain two parallel surfaces to perform optical measurements. The optical absorption spectra of the samples were collected under ambient environment. The natural radioactivity levels of the specimens were also measured using a gamma spectrometer whıch uses a NaI(Tl) scintillation detector for the determination of the radioactivity.

Keywords

• Obsidian,NaI(Tl) detector,Natural radioactivity

References

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