"B+C-Jade"

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Article 1

A green oval cabochon [Article 1] stone were submitted by customer as a “Type-A” Jadeite Jade. “Type-A” Jadeite Jade in trade is known as a jade with natural colour, and not undergone any treatment or modification through the impregnation with colourless or near colourless wax, resin, or any other agents.

We performed a standard gemological testing, and further tested with Raman spectroscopy, and result show that the [Article 1] is a jadeite jade.

The Raman spectrum matched closely with the RRUFF spectrum for jadeite

Poor surface condition of the [Article 1], along with different lustre in some pits suggested that the tested material might have been corroded by external substance, and then filled with foreign material.

FT-IR spectrum show intense hydrocarbon peak
FT-IR spectrum show intense hydrocarbon peak

Further tested with Fourier Transform infrared (FT-IR) spectroscopy, result indicated that the [Article 1] had been polymer impregnated. The presence of intense group of peaks (strong hydrocarbon peak) between 2850cm-1, and 3100cm-1, with apparent absorption maxima at approximately 2940cm-1, 3025cm-1, 3060cm-1, and 3080cm-1, is the indication of polymer impregnation. For a jadeite jade which undergone the modification through bleaching and the impregnation with resin, known in the trade as “B-Jade”.

Colour concentrations in crack lines

Under microscopic observation, found colour concentrations in gaps of micro crack lines, this is a typical indication of a dyed material. 

UV-VIS-NIR

Further tested with UV–VIS–NIR spectroscopy, and the result didn’t pickup any absorption lines in 437nm, 630nm, 660nm, and 692nm. This suggested that the colour of the [Article 1] is not natural green jadeite. It is common that most jadeite impregnation are using a coloured resin. Jadeite jade undergone impregnation with coloured resin also known in the trade as “B+C-jade”.

In some cases, standard gemological testing and microscope examination may not show enough detail to identify the treatment, and even in cases where it can, this requires considerable skill. Raman, FTIR, UV-VIS-NIR spectroscopy provides an excellent test result for further analysing on jadeite treatment. The analysis procedure yields unambiguous results.