jade, nephrite, treatments, dyed jade, gems

Liddicoat reports the identification of dyed nephrite jade at the Gem Trade Laboratory in Los Angeles, describing a carved tablet whose green coloration was established by spectroscopic examination to be artificial. The observation follows an interval during which dyed jadeite was already known to the laboratory but comparable treatment of nephrite had remained unconfirmed in its experience. The author states that dyed jadeite was first encountered in 1956 and that the subsequent appearance of dyed nephrite had therefore been anticipated. Until the specimen described in this note was examined, however, the laboratory had neither seen nor heard of such material. The object is characterized as a well-carved nephrite tablet with chrome-green mottling and is illustrated in a photograph showing its ornamental openwork design. The description of its colour records the visual appearance of the green patches; the note attributes their coloration to dye on the basis of spectroscopy. Examination specifically targeted the green areas, linking the identification of treatment to the coloured portions of the carving. Although the spectroscopic conclusion is stated unequivocally, no absorption wavelengths, spectral illustration, instrumental details, or comparison with untreated nephrite are supplied. The account likewise provides no information about the tablet’s geographical origin, the identity of the colouring substance, the method of application, or the depth and durability of the treatment. Liddicoat suggests that nephrite may not take dye uniformly and offers this as a possible explanation for the previous absence of dyed nephrite from the trade. This explanation remains tentative rather than an experimentally demonstrated property of the material. The report thus combines a definite identification of artificial coloration in an individual nephrite carving with a cautious suggestion concerning the practical limitations of dyeing nephrite. Its principal contribution is to document the laboratory’s encounter with a treatment it had expected following the recognition of dyed jadeite, while identifying spectroscopy as the means by which the artificial origin of the specimen’s green coloration was established.