Gemmological and Mineralogical Characteristics of Three Green Seal Stones

“Xi’anlv” and “Dandonglv” are used as the imitations of green larderite(“Yueweilv”)in the jewelry market recently.Mineral components, chemical compositions and microstructures of “Xi’anlv” and “Dandonglv” are investigated by using the XRD, ICP-MS and SEM, which are also compared with“Yueweilv”.The results show that “Yueweilv” is mainly composed of fuchsite, where the Cr and Fe elements lead to a slightly gray-green tone in colour; that“Xi’anlv”is mainly composed of illite with much lower Fe, and the content of elements Cr and V are much higher than those of “Yueweilv”, which may be the main reason for the green colour of “Xi’anlv”; and that “Dandonglv” is mainly composed of clinochlore with higher Fe and lack of Cr elements, which is the main reason for its dark-green tone in colour.The observation by SEM shows that the lamellar crystal of illite is small but thick in “Xi’anlv” and that the lamellar crystal of clinochlore is thin, flexible and piled up closely in “Dandonglv”.The three kinds of green seal stones mentioned here are quite different in colour, luster, weighting, and inclusion, due to their different compositions and microstructures.