Selling the Invisible: A Field Guide to Modern Marketing, by Harry Beckwith, Warner Books (252 pages) Why focus on what is invisible when you sell sparkling diamonds, vibrant colored gemstones, and precious metals? Jewelry consumers are willing to pay a premium to buy visible beauty plus more. Beckwith shares techniques that work to improve service quality, but his book primarily offers a way to think about "what business you really are in and what people really are buying," so that you understand how to position your business for profitability. For retail jewelers selling diamond engagement rings, for example, a shopper seeks services you must make visible, such as the stability to back what you sell, reflected in your long history in the community; the ease with which the client can trust you to sell what you offer, reflected in your use of reliable d