Figure 16. Chemical fingerprinting of Al/Fe vs. Ca/Na indicates the separation of jadeite (Jd) from omphacite (Omp) jade according to chemical concentration. Although the data plotted here were collected from LA-ICP-MS analysis, this type of diagram can also be adapted to EDXRF or electron microprobe data.
Figure 17. Chondrite-normalized rare earth element (REE) patterns are shown for each color of Japanese jadeite.
Figure 15. This ternary diagram for jadeite (Jd)-aegirine + kosmochlor (Ae + Ko)-Ca-Fe-Mg pyroxene (diopside + augite + hedenbergite) indicates the chemical concentration data of four green jadeites from Itoigawa-Omi by EPMA, based on Morimoto et al. (1988). Their compositions fit the jadeite range of XJd = 98.7 to 82.4. Three to 12 spots were tested on the green area of each specimen.
Figure 14. This classification of pyroxene based on chemical composition shows the relationship between jadeite and other pyroxenes in the main isomorphous substitution. Source: National Museum of Nature and Science, Tokyo.
Figure 13. A: The UV-Vis spectrum of a green Burmese jadeite (K-MYA-16) shows the characteristic chromium lines at 630, 650, and 691 nm and the sharp, narrow Fe3+ absorption band at 437 nm that is commonly seen in natural green jadeite. The Cr3+- and Fe3+-related feature generally overlaps with the spectrum of Japanese green jadeite, but the absorption intensity is much higher due to its color saturation and transparency. B: Burmese lavender jadeite (K-MYA-20) showed a dominant broad absorption band centered at 570 nm, related to Mn3+ concentration. C: The narrow Fe3+ absorption band at 437 nm, often present in Guatemalan green jadeite (M-GUA-02). The absorption of Cr3+ is not detectable in this 2.32-mm-thick sample. D: The spectrum of Guatemalan lavender jadeite (M-GUA-03) shows multiple broad bands centered at 530 and 610 nm and a weak narrow band at 437 nm. The absorption feature related to Mn3+, Ti4+-Fe2+, and Fe3+ generally overlaps with the bands observed in Itoigawa lavender jadeite. E: A vivid green Polar Ural jadeite shows an Fe3+ band and strong multiple chromium lines in the 580–700 nm range, a combination that typically produces a highly saturated green color. The concentration of Cr (maximum of 3042 ppma) is much higher than in Japanese green jadeite.
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