- 1 Murano Glassworking
- 1.1 How Murano glass is made?
- 1.2 Composition of Murano glass.
- 1.3 Murano Glassworking Thechniques
How Murano glass is made?
How is glass made? What are its features? What are the most important Murano glassworking techniques? in this page we will discover everything about the Murano glassworking.
Composition of Murano glass.
The glass is mainly composed of silica sand. Because it melts at very high temperatures (around 1750 degrees), soda (or potash) is added to lower the required melting temperature. But that is not all. Soda in fact would make the vitreous compound opaque, ruining the beauty of the glass. To overcome this problem, glassmasters add to the calcium carbonate compound, which counteracts the matting effect of the soda.
Finally, to obtain the vast range of colors offered by glass production, other chemical elements are added in different doses and proportions: oxides.
Glass, in its liquid state, is an ideal material to be worked because it has a slow solidification that allows to have a good time interval to manipulate it. It is precisely in this range, before it completely hardens, that the glassmaster can shape his object into glass.
Once cooled, the glass maintains its characteristics unchanged forever.
Murano Glassworking Thechniques
In the world of glass we can divide the processing of Murano glass into two different “moments”:
- the first processing: the process of creating real glass and processing of glass directly taken from the furnace.
- The second processing: includes all those techniques that start from an element that is obtained from the first processing.
The first processing.
The first processing includes, in addition to the actual composition of the glass mixture in the crucible, the container in which the various elements are formed to form the glass, all the furnace processes.
From the furnace molten glass is extracted which is immediately shaped, by hand or by blow, by the master glassmaker, often helped by two or more collaborators. The craftsman is required a great physical effort and great resistance to heat. For this reason most of the production takes place in winter. The techniques of the first processing give rise to the following types of glass: aventurine, chalcedony, crystal, lattimo, opal glass, glass canes, filigree and submerged.
The second processing.
The second processing includes all those techniques applied to products in glass already worked, be it the glass rod, a vase or an object created directly by the furnace. This includes lampworking, glass production, murrino glass, kiln casting, slumping, fusion glass and other “cold” processes such as decoration, engraving and grinding.
The Furnace Glassworking.
The glasswork of Murano glass in the furnace is a first processing of Murano glass.
Once all the components have been added in the correct proportions and brought to the melting temperature of 1400 ° c, the glass is created .. once it is ready, the vitreous mass is brought to a temperature of about 1000 ° C to be processed more easily.
The master glassmaker extracts the glass from the crucible thanks to a shovel, and here the real work begins.
For such a work, by breath or by hand, the artist is not alone. There are collaborators who help him manage the vitreous mass and the instruments. Generally these collaborators are three or four highly specialized people each in a different phase of the process.
the serventin takes the first bolus of vitreous mass and prepares it by blowing and working it on the “bronzin” (an iron plate used as support during the working). once the right compactness is reached the red-hot repeats this operation several times until reaching the desired quantity of glass.
At this point the worked and homogeneous glass mass is passed to the servant who will manipulate it and bring it to the exact size to be delivered to the glassmaster.
At this point the master has little time to create his objects before the glass cools down. Once finished, the artistic glass works are placed in cooling ovens to bring them to room temperature in the longest possible time. Otherwise the glass would risk breaking.
The productions that are made in the furnace are generally medium-large pieces: sculptures, vases and chandeliers.
the “Lume” glassworking
The lampworking ( called “Lume”) is one of the most important and famous techniques of Murano glass working. At the “Lume” (the original Venetian term is feminine) are produced small artifacts that cannot be made by blowing in the furnace.
like the famous “Venetian beads”, pendants, rings, and all those small-sized objects commonly grouped with the term “Murano glass objects”.
The ancient “lume” has now been replaced by the more modern gas (or propane) and oxygen torch. The torch produces a more or less intense flame in which the master glassmaker can heat the glass canes and thus bring the material to the right temperature to be worked. the lampworking allows the creation of objects both full and “blown”.
and from here, depending on the skill and creativity of the artist, an infinite panorama of objects can be created. famous are the “murano glass zoos”, all that production line of small glass animals, more or less stylized.
Other typical productions are all those figures typically designed for the tourist market: Venetian gondolas, perfume bottles, mined aquariums, fantastic characters and other objects used as decorations or favors.
Murano glass beads
The lamp beads are made starting from a massive, transparent or full-colored glass rod, and working it with the torch. At the heat of the flame the glass recasts and creates a thread that is wrapped around a thin metal rod (or copper tube). A sort of ball of molten glass is thus formed which is worked and shaped with pliers.
During these processes other components can be added to the glass to decorate the pearls: gold leaf, silver leaf, aventurine, shiny mineral and filigree or zanfiric glass canes. The pearls can be worked completely by hand or with special bronze molds that give the pearl the desired shape.
The beads are then cooled slowly to avoid breakage. For this reason they are placed in special ovens called muffles.
To remove instead the metal bars on which the pearls have been created there are two techniques.
The first is to apply, before starting to create the glassware. On the metal rod a specially created batter. This batter prevents the molten glass from sticking to the bar, and promotes the sliding of the pearl on it.
The second technique involves the use of copper tubes. After the pearl has been created it is cooled, it is immersed in the acid which, by dissolving the copper tube, leaves the hole free.
The different glass bead processing techniques
Lampwork beads can have numerous technical variations. Among the most interesting and most “Venetian” there are certainly the techniques of gold leaf and silver leaf. This technique is realized by forming a first nucleus of molten glass and, with this, going to take the gold or silver leaf by rolling and subsequently including everything with a second state of transparent glass.
To prevent the gold or silver leaf from melting or being ruined, 24 carat gold sheets and pure silver are used.
Another very important technique is that with which small colored glass tubes are applied, the murrine, on the main core. In this case the murrine can be placed one by one according to a predetermined pattern or they can form a continuous surface obtaining a “millefiori” or “mosaic” pearl.
Another typically Venetian technique is that of the flowered pearl “Perla Fiorata”. At an initial glass core, decorations are made with a thin colored glass thread called “vetta“. With the summit you can create geometric and stylized decorations, or real floral designs. Hence the name “fiorata pearl”.
Glass fusing processing
Glassworking using the glass fusing technique is perhaps the least known and least characteristic.
It is a second processing and is done by “cooking” in special ovens.
The glass, previously prepared in plates, is placed in overlapping layers. Subsequently these layers are baked and brought to a temperature that will melt the glass plates. The slabs joining together will give life to a new object.
In addition to the slabs, small pieces of “murrina” cane can be added to create decorations.