Murano Glass square about 18mm in rounded on the edges as it is hand formed. These Murano Glass beads make great little earrings or bracelets. The sparkle in these is provided by the use of aventurina which is copper particles suspended in the glass. This one includes a sash of both 24kt gold foil and .925 sterling silver which is encased in clear Murano Glass. The size is approximately 18mm square and about 7mm thick with a 1mm center hole. Authentic Venetian Glass Beads.