All our murrine are made of Murano glass (coefficient 104) and can be used with glass sheet, rods and grits of the same coefficient. Please note: The dimensions are variable. Per description you will find the minimum and maximum diameter that you will find Sopra the package. Con the site https://bicchieri64196.xzblogs.com/68120893/non-nota-dettagli-circa-vetro-colorato