NEW GEMS: Two jewelry houses have heightened their profiles at South Coast Plaza in Costa Mesa, Calif. Both Cartier and Chopard have more than doubled the size of their stores at the shopping center. The new Cartier store, which increased from 2,831 to 6,008 square feet, is due to open Tuesday with a facade that is unique in the U.S. containing the brand’s double C logo backlit with warm lighting. The interior features a concept by architect Bruno Moinard that has wood paneling and flooring, glass displays trimmed in bronze and a custom Windfall chandelier at the entrance. For the store’s opening, customers will be able to view Cartier’s Panthère necklace with a 70.34-carat yellow sapphire, 1,844 cultured pearls, 853 brilliant diamonds, emerald eyes, onyx spots and an onyx nose set in platinum. The 2,250-square-foot Chopard store, which the brand feted with a cocktail soirée on Tuesday attended by Chopard’s Marc Hruschka, Henry and Elizabeth Segerstrom, and Camilla Belle, is the first on the West Coast to incorporate the brand’s new global design concept by architect Thierry Despont. Originally unveiled in 2007 at Chopard’s Madison Avenue flagship, the design includes wood accents and fireplaces.