Swarovski Necklaces. SKU: 5661187. Color: Blue. Swarovski Matrix Blue Round Cut Crystal Tennis Necklace. This Matrix Tennis necklace is embellished with vivid blue tone round crystals set on a row of rhodium plated chain. Length: 16 1/8 inch, Width: 1/4 inch. Clasp type: Tongue closure with safety clasp. Collection: Matrix Tennis.