The London-based jewelry brand Annoushka has arrived in the United States, debuting earlier this month at the Saks Fifth Avenue flagship stores in Beverly Hills and New York. To celebrate its stateside debut, Annoushka has brought two of its collections to Saks Fifth Avenue: One of a Kind and Annoushka/24. The former, a limited collection of pieces that spotlight chunky colored gems, includes a pair of sapphire-and-ruby earrings priced at $37,500. Annoushka/24 comprises four themed subcollections: Arabesque, C…