To help ensure that you are buying authentic crystals from Swarovski, the Swarovski seal comprises the latest security features.Apart from its hologram effect, every seal has a unique identification number that can be found directly below the seal on the front of the tag or sticker on which the seal is applied. The 16-digit code identifies the brands that are using genuine Swarovski crystals in their finished products, providing proof of the origin and premium quality of the crystals used.