Abstract:Guatemalan "blue water" jadeite and Myanmar "oil green" jadeite were analyzed by means of microscope observation, thin section observation, X-ray powder diffraction, laser Raman spectrum, and scanning electron microscope analysis. The authors tried to compare these two jadeites in conventional gemological characteristics, structural characteristics, impurity minerals and chemical composition. The results show that the jadeite grains of Guatemalan "blue water" material develop homoeoblastic structure, and the major mineral is jadeite, with a small amount of omphacite, the jadeite particles show the rhythmic zoning with 2~3 layers, and the omphacite occurs as euhedral grains, residues of metasomatism or filling material along the micro-crack, in which the white punctate mineral is albite, and the green punctate mineral is a mixture of aegirine-augite and omphacite. The jadeites in Myanmar "oil green" jadeite have coarse particles and a columnar granular mosaic structure, with relatively uniform sizes. The mineral has pure jadeite and mottled omphacite as impurity mineral, the jadeite particles of Myanmar "oil green" jadeite show the rhythmic zoning with 3~5 layers, and the omphacite grains fills the gap of jadeite particles in vein shape or is replaced by jadeite crystals in island shape. Meanwhile, the content of CaO in Guatemala "blue water" and vein omphacite are higher than that in Myanmar "oil green" jadeite. In addition, with the existence of aegirine-augite, it is inferred that there may be differences in Ca and Fe content in the crystal environment of jadeite from the two producing areas.