The era of high-low living is upon us. In practice, it’s the ability to master the pairing of items made for the few with those made for the many. For example, a favorite blogger dons a limited-edition Chanel handbag to accessorize a Zara dress, or an interior designer pairs a custom couch with a lamp from IKEA. But do the same rules apply to jewelry?  Heck yeah! What was once taboo—a fine jewelry store carrying fashion or bridge merchandise—is now de rigueur. For one thing, the rise of casual lifestyles demands that retailers be ready to serve clients for whom jeans and sneakers are a daily uniform. For another, the designers themselves offer both high-end and entry-level collections. As the number of specialty boutiques that carry jewelry, clothing, and accessories continues to grow (see “Lifestyle and Substance”), customers are in fact relying on one-stop shopping for all