PICKING A JEWELER By Mike Seltzer      There is no better way to commemorate one of the most important times of your life than with jewelry. Diamonds and gold have been a symbol of undying love for centuries and with good reason. Few purchases in life are as important or as lasting. When you buy a car, it begins to depreciate the instant you open the door. When you buy a diamond, its value starts to appreciate almost immediately. The time when a couple is making a life long commitment to each other is often the first time they have a need to seek out a good jeweler.