After a year-long renovation, Cartier reopens its venerable doors this summer at 653 Fifth Avenue. In 1917, Pierre Cartier pulled off the Manhattan real estate deal of the century by trading $100 in cash and a double-strand necklace of 128 natural pearls for this Renaissance-style townhouse on the southeast corner of 52nd Street. Inside the "new" Cartier, you will see not only contemporary creations of the high quality that has kept the house in the forefront of the jewelry world for more than 150 years, but timeless designs that link the company to its illustrious past. An example is Cartier's "panther-skin" ornament in onyx and pavé-set diamonds, which debuted on the bezel of a woman's wristwatch in 1914. Eventually the motif developed into a representation of the animal itself, which became a cult item under the auspices of Jeanne Toussaint, Cartier's director of haute joaillerie from 1933 and guiding force behind the firm's design for three decades. Toussaint (nicknamed Panther) might indeed be pleased to know that her signature animal and other wildlife designs that she inspired are still in style.