Ss30 Swarovski flat back 6.5mm rhinestones from Swarovski's Crystallized Elements range are regarded as the highest quality rhinestones in the world. These highly polished cut glass flat back's have a higher lead content than other crystals of a similar nature and as such are extremely sparkly when in contact with light. The 2028 Xilion Rose is multi faceted and comes with a silver backing to enhance the rhinestones dazzling effect and provide a better surface for adhesives to bond to when attaching them to a surface. 6.5mm rhinestones are very popular for dancewear as they are larger in diameter than the ss16 and 20 crystals and as such require fewer crystals to create that dazzling effect.