Abstract
In this study, we conducted heat-treatment on freshwater cultured pearls at various conditions in other to improve their color. Also, after heat treatment, we used the UV-Vis, ED-XRF and SEM to investigate changes freshwater cultured pearls' color, composition and internal structure. UV-Vis analysis showed the reflectivity of samples increased at most heat-treatment conditions although the reflectivity decreased at a certain temperature and duration. At $100^{\circ}c$/8 h, $120^{\circ}c$/6 h and $140^{\circ}c$/4 h, the reflectivity increased highest. In proportion to reflectivity increase, freshwater cultured pearls' color was improved. Ca, Mn, Sr and other micro elements were found from ED-XRF analysis. However, changes in composition of elements were not detected. It was found that the content of Mn in freshwater cultured pearl is higher than other micro elements. From SEM analysis, aragonite's shape was shown in narce and some of the narce were condensed after heat treatment.
본 연구에서 우리는 다양한 컬러의 담수양식진주(화이트, 오렌지, 퍼플 등)을 사용하여, 담수진주의 컬러를 변화시켜 가치향상을 목적으로 다양한 온도 및 시간별로 열처리를 실시하였다. 진주의 손상을 최대한 막고 컬러를 향상시킬 수 있는 최적의 조건(온도 및 시간)을 정립하여, 그에 따른 진주의 컬러변화, 광택, 성분분석, 내부구조 등의 변화를 UV-Vis, ED-XRF, SEM 등을 사용하여 비교 관찰하였다. 결론적으로 우리는 열처리를 통하여 담수양식진주의 컬러와 광택 및 상품가치를 높일 수 있는 가장 적합한 조건을 제시하고자 하였다.
