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JADEITE JADE — Beads of an unusual color: An attractive necklace of predominantly brown-and-white (with lesser amounts of green) variegated beads (figure 10), which a client purchased recently in Tucson, was submitted to the East Coast lab for identification. We identified the beads as jadeite on the basis of standard gemological testing. Although many jadeite boulders have a brown outer layer (or “skin”; see, e.g., figure 6 of Winter 1995 Gem News, p. 278), where the color is due to staining by an iron compound, we do not recall ever having seen beads with this agate-like appearance. Some years ago, we encountered solid-color brown jadeite cabochons that we believed were the result of such natural staining. More recently we have seen jade of a fairly uniform brown color that appeared to be the result of some type of dyeing process. However, the variegated color of these beads indicates natural color. The fact that a number of the beads in the necklace were banded with grayish green jadeite further supports the conclusion that the color was probably natural and that the beads were cut from near the outside layer of a naturally stained jadeite boulder. Of the beads that we tested, all exhibited a 437 nm iron line and spot refractive index values within the normal published range for jadeite (about 1.66). For the most part, the beads were inert to both long- and short-wave ultraviolet radiation. The attractive brown-and-white variegated color suggests that these beads had not been subjected to bleaching and impregnation, since the brown veining would most likely be removed during such treatment. Infrared spectroscopy on a few of the beads confirmed that they were not polymer impregnated. [Figure 11. The green spherules in this polymer-filled cavity in a jadeite bangle make the filler much less conspicuous. Note also the many gas bubbles in the polymer. Magnified 25×.]