FTIR을 이용한 브라질 Itabira 지역 에메랄드의 분광학적 특성 연구

Application of FTIR on the Study of Spectroscopic Characteristics on Emerald from Itabira, Brazile

  • 임예원 (경북대학교 자연과학대학 지질학과) ;
  • 장윤득 (경북대학교 자연과학대학 지질학과) ;
  • 김종랑 (경북대학교 자연과학대학 지질학과) ;
  • 김형수 (경북대학교 사범대학 지구과학교육과) ;
  • 김종근 (대구산업정보대학 보석감정학과) ;
  • 김정진 (안동대학교 지구환경과학과)
  • Lim, Ye-Won (Department of Geology, Kyungpook National University) ;
  • Jang, Yun-Deuk (Department of Geology, Kyungpook National University) ;
  • Kim, Jong-Rang (Department of Geology, Kyungpook National University) ;
  • Kim, Hyeong-Soo (Department of Earth Sciences Education, Kyungpook National University) ;
  • Kim, Jong-Gun (Department of Gemology, Daegu Polytechnic College) ;
  • Kim, Jeong-Jin (Department of Earth and Environmental Sciences, Andong National University)
  • 발행 : 2008.12.30

초록

현재 에메랄드의 중요한 산지로 자리 잡아가고 있는 Itabira 지역 에메랄드의 분광학적 특성을 연구하기 위하여 에메랄드를 C-축에 수직, 수평인 방향으로 각각 절단하였으며, $H_2O$ 관련 범위의 좀더 세부적인 피크 관찰을 위하여 KBr로 압축한 pellet시료를 만들어 적외선 분광분석(FTIR) 실험을 수행하였다. $H_2O$ 관련 범위에서 $5,271\;cm^{-1}$, $1,638\;cm^{-1}$ 피크가 나타나는 것으로 보아 본 시료는 Type-II에 해당함을 관찰할 수 있었으며, $H_2O-Na-H_2O$ 배열 형태를 가지는 Type-IIa에 해당하는 피크가 아주 강하게 나타나고 있다. $H_2O$ 관련 범위를 제외한 특정 범위에서는 $CO_2$, Cl 피크 등이 관찰되었으며, 적외선 분광분석 법을 이용하여 타입의 분류뿐만 아니라 상대적인 피크 강도 비교를 통하여 $Na_2O$ 함량 또한 예측 가능한 것으로 사료된다.

Emerald deposit located on Itabira, Brazil is one of the major one in the world. We applied three different analytical approaches on Itabira emerald samples, (1) perpendicular to the c-axis, (2) parallel to the c-axis, (3) emerald pallet mixed with KBr, using Fourier Transform Infrared (FTIR) spectroscopy, to understand and compare spectroscopic characteristics of three Itabira emerald samples. Occurrence of $5,271\;cm^{-l}$ and $1,638\;cm^{-l}$ absorption peaks within $H_2O$-related range indicates that the samples belong to Type-II emerald. These emerald samples also display strong absorption peak generated from Type-IIa emerald preserving $H_2O-Na-H_2O$ sequence. $CO_2$- and Cl-related absorption peaks observed within specific range except for $H_2O$-related range. These observations and results suggest that FTIR analysis can be used for not on1y classification of emerald types, but also prediction of $Na_2O$ content within the emerald through comparison of relative peak intensity.

키워드

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