JADEITE - Canadian Institute of Gemmology

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Cabochons. As was noted above, the tendency is to cut better quality rough jadeite into
cabochons. Ng and Root (1984: 41) discuss what to look for in assessing the quality of a cabochon
beyond the quality of the jadeite itself:
First, we look for well balanced, pleasing proportions of length to width ratios which would
be most useful in a ring stone. Next, the cabochon should not be too high or thick, nor be
too thin. The half-moon is an ideal shape, with the height not being more than half the
length... The cabochon should also have an only slightly rounded girdle, or edge, for good
mounting. Moreover, the bottom of the stone should be slightly curved so as to form a well
balanced lightly convex surface.
In the case of jadeite that is less transparent, the ideal in a cabochon is one cut with a flat base, since
such curvature, as mentioned above, only adds to the weight of the stone without influencing its
beauty. Size may also be a factor in assessing a cabochon. Ng and Root (1984: 48) comment that
since people in Asia tend to be smaller than people in the West, very large cabochons "may not be
as much sought after" in Asia as in the West, where "persons of larger build may well find those
larger sizes the most desirable." The most common size of cabochon that is used as a standard for
pricing is 14 x 10 mm. Larger sizes that may be viewed as more valuable include 15 x 11 mm, 20 x
15 mm, and 22 x 16 mm. Smaller sizes, ranging from 11 x 9 mm down, tend to be less valuable.
Ng and Root (1984: 42) also discuss the ideal way of mounting jadeite cabochons in jewelry.
The cabochon should be mounted in a setting with a "small hole under the center of the stone." The
hole helps to increase the amount of light returned from the stone. It also serves practical purposes
in assessing the stone. It allows for the shape of the back of the stone to be examined and, in
particular, to see if the stone has been hollowed out. A stone that is not mounted in this way should
be examined with particular care.
In addition to oval cabochons, pieces of jadeite jewelry may also be carved into heart, marquise,
pear, and teardrop shapes. Ng and Root (1984: 47) comment that the heart shape is the second most
popular shape in Asia after the oval and that it too should have a rounded bottom. The ideal
dimensions for a marquise cut piece is a length to width ratio of two to one. As for pear and
teardrop shapes, "they must be well-tapered, cylindrical in form and pleasing in proportions."
Beads. While the jadeite used for beads tends to be of lesser quality than that found in the best
cabochons, this is certainly not always the case and very fine jadeite is sometimes cut into beads.
Hughes, Galibert, et al (2000: 20, fig. 19) illustrate a necklace (known as the "double fortunate"
necklace since its owners had doubled their fortunes every time the boulder was cut) auctioned by
Christie's in Hong Kong in 1997 that sold for about US$9.3 million. It featured some of the ideal
characteristics looked for in a necklace: "Uniformity of a fine 'emerald' green color, superb
translucency, size, and symmetry all come together." This necklace is comprised of twenty-seven
beads ranging in size from 15.09 mm to 15.84 mm. They were all cut from the same portion of
rough stone.