Gemmological Study on Chicken-Blood Stone from Changhua

The mineral components,morphological characteristics and chemical compositions of the "Di" and "Blood" of the chicken-blood stone samples from Changhua are studied by means of XRD,LRM,SEM and EPMA with rock slick.The results show that the mineral combinations are quite different among the "Ying Di""Ruan Di" and "Dong Di" of the chicken-blood stone samples.The "Di" is mainly composed of dickite being squama-like.As quartz increases,especially alunite,the rigidity of the "Di" becomes harder.The crystal granularity of the dickite in "Dong Di" is larger than that in "Ying Di" of the chicken-blood stone samples,and the space direction of dickite in "Dong Di" is not good as that in "Ying Di" samples.The "Blood" in the chicken-blood stone sample is composed of fine hypidiomorphic—altotriomorphic cinnabar minicrystal aggregation,where the colour is related with the assemble state of cinnabar crystal and its impurity composition which has correlation with the content of Se.