We love that each piece from CVC Stones' collection is completely unique - "There is only one such beach stone with that diamond arrangement in existence, " says founder Charles de Viel Castel. This 18-karat gold 'Olivia' necklace features a rounded pebble encrusted at the center with a gleaming 0.25-carat diamond and along the edge with 0.045-carats of smaller diamonds for additional sparkle.