Study on the Correlation between Fe2+ and Peridot's Yellow Green Color and Quality Evaluation of Color Based on CIE1976 L*a*b* Uniform Color Space

Abstract

Abstract. Based on CIE1976 L * a * b * uniform color space, 54 peridot samples' color were measured under D65 light source. The component analysis results showed that all samples are forsterite and chrysolite. It showed that with the increase of Fe 2+ , peridot's color turns to yellow. But Fe 2+ has no significantly correlation with chroma. By applying clustering analysis and discriminant analysis, the results showed that peridot's yellow green color were divided well into eleven categories by K-means clustering analysis, and ANOVA showed L * , a * and b * values among various categories were significantly different (sig＜0.001). A linear discriminant function model of the eleven categories of peridot's yellow green color was established by Fisher discriminant analysis which had excellent performance of discriminant with the model checking accuracy of 98.1%. Based on lightness and chroma, peridot's yellow green color was graded into seven levels, consisting of Fancy Vivid(FV), Fancy Intense(FI), Fancy Deep(FDe), Fancy Light(FL), Fancy Dark(FDa), Light(L), Very Light(VL).