At the inner core of a Swarovski pearl is a round crystal bead nucleus)which is then coated with the pearl coating. These crystal pearls have a thicker coating & richer luster that does not scratch or chip as easily. Swarovski crystals, like most other crystals, contain lead oxide.Lead creates the refraction of the crystal with the maximum refraction at 30-32% lead content. Lead also adds to the weight of the crystal giving it a more substantial feel. Austrian Swarovski crystal contains approximately 32% lead. Full lead crystal must contain above 30% lead oxide content in order to be consider full lead crystal.