Would Tiffany & Co. really engrave a ring from a box of Cracker Jack? “Vision and Virtuosity” may not answer that question, but it will clue viewers in to Tiffany’s greatest diamonds, the special objects in its archives, the company’s love of color—which begins with its trademark robin’s-egg blue and extends to a rainbow of gemstones—and its iconic designers, from Jean Schlumberger to Elsa Peretti. A glittering history, starting in 1837. —L.J.