Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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Color enhancement of Australian natural sapphire by the hydyothermal method

수열법에 의한 호주산 천연 사파이어의 색상 개선

  • Kim, Hee-Seung (Department of Gemological Engineering, Graduate School, Dongshin University)
  • 김희승 (동신대학교 대학원 보석공학과)
  • Published : 2006.12.31
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Abstract

The significant color enhancement in low quality Australian natural sapphire has been achieved by a hydrothermal method. The optimal conditions for the color enhancement of Australian natural sapphire were as follows; hydrothermal reaction temperature: $320{\sim}350^{\circ}C$, duration : 3 days, hydrothermal solvent: 2 M NaOH solution. After the hydrothermal treatment, Australian natural sapphires of transparent colors were obtained, and their grades were found to be improved from commercial to middle/top grade by value chart analysis.

본 연구에서는 수열법을 이용하여 저품질의 호주산 천연 사파이어에 대한 색상개선을 행하였다. 호주산 천연 사파이어의 색상 개선에 대한 최적의 수열처리 조건은 다음과 같다. 즉, 수열반응온도 $320{\sim}350^{\circ}C$, 반응시간: 3일, 수열용매: 2 M NaOH 수용액이다. 이와 같은 조건하에서 수열 처리한 후에 투명한 색상의 호주산 천연 사파이어가 얻어졌으며 천연 사파이어 가치 차트로 비교한 결과, commercial 등급이 $middle{\sim}top$ 등급으로 색상이 개선되었음을 확인하였다.

Keywords

References

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