The manufactoring of Murano glass and beads

Many are the processes and techniques that have been invented over the centuries, acquired and handed down by Murano glass masters. All our pearls are manufactured by artisans who have their headquarters in the famous island of glass.

The leaf is a metallic sheet (of gold or silver) generally of a few centimeters of side but so thin that from 20 grams of gold can be obtained up to 6 cubic meters of lamina! Used both for blown glass and glass with the submerged technique, it was introduced in Murano in the second half of the fifteenth century and taken up again in the second half of the nineteenth. In the blown glass the hot glass post is covered with the gold or silver leaf and then covered with a further withdrawal from the crucible. Following the definitive blowing, the metal leaf shatters inside in small fragments or in a fine dust, with very particular reflections and elegance effects.

It is a very ancient technique, already applied to the Roman cameo glass. By the word “submerged” we mean the particular technique used by the furnaces in the production of artistic glasses and consists in coupling, in hot, different shades by immersing the thick blown glass in crucibles containing different colors (earthenware or metal vases used in furnaces and foundries – usually in the shape of an inverted truncated cone – to melt metals, alloys and to produce chemical reactions at high temperatures).

Revolutionary technique dating back to the first century BC. Thanks to the rapidity of execution, the blowing allowed the diffusion of glass containers in the modest classes. It was invented in the nearby Mediterranean East and developed in Islamic, Roman and Venetian glassworks. With the invention of glass lamp, a new trade corporation was born in Venice, that of the “supialume”, which produced pearls by means of an oil lamp on which they blew with a bellows and empty objects blown inside.

Murrina is obtained by combining sections of polychrome glass canes by welding them together with the heat of the oven (for softening and adhesion). It is used in multiple processes, including the mosaic pearl. Once the “murrina” cane is cut into disks, the artisan makes glass pour around a small iron rod, thus creating a soul on which a certain quantity of preheated discs is stored. When the heat of the flame makes the composition soft at the right point, the modeling of the pearl will take place through the chosen clamp.

Invented in Murano between the end of the fifteenth and the first half of the sixteenth century to decorate the blown glass crystals. The processing of filigree blown glass involves the use of crystal glass rods (called canes) containing colored glass threads (“lattimo”), smooth or spiral. The two traditional types of filigree are the “reticello” or “double” watermark, with mesh wefts, and “retortoli” filigree, with spiral threads. New types of filigrees have been created in Murano in recent decades.

It is a pure and transparent glass obtained by bleaching with manganese dioxide, purification of melting ash and special procedures applied to the conduct of the fusion. Discovered in the mid-fifteenth century, the crystal appears as a colorless glass particularly suitable for complex work requiring long periods of manipulation by the master glassmaker.

Aventurine glass is a process invented in Murano around 1620. The first recipe to create aventurine is found in a manuscript by Giovanni Darduin of 1644, although already in a letter of 1614 it speaks of “a kind of stone with golden stars inside”, from which also its further name of “stellaria” (from “Types of glass and glassmaking techniques in the nineteenth century”, Museo del Vetro, Venice). The aventurine glass assumes, probably, the name also from the circumstance for which its difficult realization is to be considered a real “adventure”. It is a brown-colored glass paste that comes in the form of blocks. Inside it is immersed brilliant specks of copper with brilliant metal oxides that create an effect similar to that of aventurine quartz. The processing, very complex and long, ends with the precipitation of the metallic copper which is thus completely separated from the base glass, dispersing itself in very minute crystals which tend to give the material a brown-red shimmer with golden reflections. It is still used by the “perlere” (the producers of pearls), ground in crushers of various thicknesses called “pestaccio” or “spolvero” or pulled into “peaks”, of thin metal wires used for decorations.