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The simplest thing: watch who the gift is for. If she's a big fan of jeans and chunky platform sneakers, you're almost certainly better off looking at the trendy "casual" sterling silver rather than the limited-edition handmade enamel line. If her lifestyle, albeit with some differences, does not differ from the “home-work-home” scheme, give her something that she will feel comfortable in the office. Thinking of gifting something a little more "festive" that turns her into the star of the party with the wave of a wand? Look at your joint photos from birthdays: what does she prefer to wear “on the way out” - spectacular earrings or rings with bracelets?