Crystal, There are two basic kinds of crystal - rock crystal and man-made. Rock crystal, the common name for the silicate mineral, quartz, which is a semi- precious stone that occurs in nature. Man-made crystal is produced from a mixture of quartz and, soda, potash, and lead oxide. Swarovski is a man-made crystal. Oddly enough, rock crystal has nowhere near the color or brilliance of manufactured crystal. You will receive 5pcs of Silver plated, Better quality, faceted crystal glass beads for Biagi, Tedora, Chamilia, Bacio,Charm bracelets, etc. Beads size is approx. 9x14mm, Inner diameter of the core is about 5mm, 9 grams.sku# zpa0200