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The monitoring of contaminants in imitation jewelry has become important nowadays due to the high amount of products sold worldwide. Due to the complexity of the sample matrix (composed mainly of metals in high concentration), sample analysis can be very challenging. One interesting alternative for this purpose is the use of photochemical vapor generation coupled to inductively coupled plasma optical emission spectrometry (PVG-ICP-OES) due to the ability of separating the analytes from the sample solution prior to analysis; additionally, it is considered an eco-friendly approach if compared to other vapor generation techniques. Thus, this work presents the development and application of a PVG-ICP-OES system for the determination of Hg and Pb in imitation jewelry after sample dissolution in hydrochloric acid. The PVG system was built with two UV lamps (254 nm), a quartz capillary reactor, and a glass gas-liquid separator. Acetic acid concentration and UV exposure time were optimized using a central composite design, as well as the carrier gas flow rate and the radiofrequency (RF) power for the ICP-OES. The optimum conditions were achieved at 30% v/v acetic acid, 60 s reaction time, 0.035 L min−1 carrier gas flow rate, and 1310 W for RF power. The influence of the sample matrix and chemical modifiers were studied, where it was found that the presence of the sample matrix may cause suppression of the analytical signal. The accuracy of the method was evaluated by recovery tests, which ranged from 88 to 102%. The detection limits ranged from 1 to 3 mg g−1, allowing the monitoring of Hg and Pb in imitation jewelry.

This article explores the cause of the so-called 'coffee-and-cream' or 'milk-and-honey' effect in chatoyant cabochons. This secondary phenomenon, observed in some cat's-eye gems under oblique lighting, is seen as light and dark halves of the stone located on either side of the bright chatoyant 'eye'. The half nearer to the light source appears dark, while the further side is suffused with a creamy brightness. It is demonstrated that the creaminess is caused by reflections from fibres deeper in the stone than those that cause the 'eye', and that it is impossible for such reflections to reach the observer from the side of the stone that is closer to the light source.

NEW YORK — \"Do you like jewelry?\"

\"I HAVE THIS OBSESSION with what women wear in Russia,\" said Rachel Zoe, as she fluffed an ivory fur hood atop a mile-high model wrapped head to toe in Zoe's fall collection. \"The funny thing is that I don't know because I've never been there. But it's what I dream about.\"