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The main tool in the Murano glassmaking is the oven : a closed room, with walls made of refractory material, provided with openings, from which we extract the glass at temperatures of 1000 degrees Celsius. Inside the oven there is the so-called "crucible", a refractory material container, which contains the raw materials mixed with each other. To pour the mixture of raw materials inside the oven is used the "cazza da infornar", later with the "cazza da missiar", one in iron instrument equipped with a long handle which ends with a sort of spoon, transporting the molten glass from one crucible, as a last step using the "cazza da traghettar" an instrument in the shape of the blade that serves to raise the already molten glass from the furnace and move in water-filled containers. Member of Murano glass for the machining tools are characteristic: the best known tool is the "blowpipe", a metal pipe used to blow the air into the melt just taken from the oven. Every teacher has his own instruments which always brings. Often they are also used of wood or cast iron molds (open or closed), which are based on a very ancient technique. Over the centuries within the furnace for glass blowing instruments the same, evidence of craftsmanship remained and tradition that a Murano glass product even encapsulates . An old proverb Murano says, "Good tools are useful, but good hands are better", strengthening the artistic nature of the glass making process, which is based on the skill of the craftsman rather than the use of special tools.
Small wooden axis, linked to a master of the thigh (or both), which serves to support the barrel during processing, then replaced by the "scagno" arms.
Shaped clamp and different sizes used to perform modeling operations, choke, cut and decoration of hot glass processing
Canna da soffio
Iron pipe perforated in the longitudinal direction with one of the two ends of slightly conical shape. It is used to pick up the glass from the crucible, for blowing and shaping freehand object or with the use of a mold.
Also called "padella" It is a refractory material container (formerly referred to as "tera" or "creda"), located within the furnace, which contains the mixture of raw materials for melting.
iron shaft filled with whom the master glassmaker supports the glass when it works in the attached to the blowpipe.
Scanno o Scagno
It is a three-legged stool on which sits the master glassmaker. It is a characteristic feature of glass making in the Mediterranean area.
A document dating back to 1313 testified that in the European glass production, the stool is not used, because the master is standing up.
Scissors, of various shapes, used to cut the glass in excess still hot.
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Secondary processing or "Cold" processing includes all the techniques executed without melting glass in the oven.
The "conterie" are glass beads rounded or sharp edges, obtained by processing "a lume" dissecting perforated tubes pulled into the furnace for about ten meters. The glass rod unperforated is softened by the heat of the fire escaping from a torch, subsequently is wound around a metallic tube which gives the pearl the desired shape and finally decorated with the use of polychromatic glass. The conterie are different from those worked in the past that were called margarite. Their work was introduced in Murano in the thirteenth century by Cristoforo Briani and Domenico Miotti. By their numerous pupils born flourishing industry still active.
Enamel Decoration "Decorazione a Smalto"
The technique of glass decorated with enamel involves the use of colored compounds obtained with powders of opaque low-melting glass and finely ground transparent,
applied with a brush on the surface of the glass to realize a decoration which can assume abstract silhouettes, vegetable or figurative.
The decorated object is subsequently subjected to a thermal cycle which does not exceed 500 ° C, in this way the glass applied with a brush,
softening, it adheres permanently to the glass surface of the support.
This type of technique has Eastern origin and was introduced in Venice in the last decade of the thirteenth century with a large fortune in the Renaissance.
With "millefiori" is defined as a perforated or non-perforated barrel which has inside several concentric glass layers of various color and form, usually in flower or star.
The processing first involving the use of open molds that imprint from time to time the different shapes depending on each of different color layer and then the circulation of the barrel along tens of meters.
A special type of millefiori cane is the rosette, which dates from the fifteenth century, characterized by motifs in star white glass, red and blue, in alternate layers.
The millefiori cane is usually cut into sections called murrine. The segments obtained from a perforated barrel, after being bevelled, can become the pearls.
While the non-perforated sections may be put together and fused to the heat of the oven so as to prepare cooked or bowls and if fused to the bottom of a small mass of crystal hemispherical,
of pressacarte or papier-presses.
The grinding is a technique, it remained unchanged for many years, which allows to dig the glass and is carried out in several stages.
The first phase involves the use of a very crude wheel comprising silicon carbide grain "80", the second stage consists in adjusting the incision previously performed with a wheel,
always in silicon carbide, but more fine-grained "220", the third stage acting with the moltaura and smoothing the incision through the use of a wheel natural sandstone.
In the fourth and last step the object is passed back with a cork wheel impregnated by a mixture consisting of pumice stone and water with the purpose of polishing the incision.
A work done we proceed to clean and make the bright object with a wet rag wheel of cerium oxide and water.
The origins date back to the Renaissance of Venetian mirror. The mirror processing is based on a glass plate, with a part coated with aluminum or silver,
which produces an image by reflection of the figures which appear in front of it. Only in the late twelfth century and the beginning of the thirteenth there was the spread of glass mirrors with a metallic coating and,
with the Renaissance, Venice and Nuremberg became the renowned centers for the production of these items.
In the sixteenth century the most popular way to make a mirrored glass surface consisted in applying a thin reflective metal layer, often a mercury and tin alloy (amalgam).
Later in 1835 Justus von Liebig discovered the chemical with silver glass coating process that gave rise to the production techniques of today's mirrors.
The procedure is to spray, under vacuum, a thin layer of aluminum or silver on the lower part of the glass sheet and wait for the reaction to electrolysis.
The metal layer deposited on the opposite side to the reflective is covered by a paint for protective purposes.
It is an ancient technique, which also includes the mosaic glass. of different color glass sections are juxtaposed on a ceramic fiber plate and melted in an electric furnace so as to obtain a multicolored vitreous mosaic or said fabric murrina glass. They are arranged on the plate or fragments of different colored glass beads that blend with the basic vitreous support. The operation can be repeated several times by overlapping the colors and creating a three-dimensional decoration.
The murrino glass is a technique among the oldest, it is a second processing which consists of a vitreous composite plate by welding with heat the tiles of different color glass cut from polychrome rods,
the plate is subsequently molded with the use of a mold in fireclay and can also be further modified by taking the form of a vase.
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First processing includes all the techniques applied to the raw material, sand and other minerals to obtain different kinds of Glass
The term "Avventurina" describes a glass invented in Murano around 1620 which has enveloped the mass, at first sight, countless specks of gold, in fact concerned with tiny copper crystals.
The secret of avventurina composition, held for centuries by a few glass masters, is to add completion of the merger,
appropriate quantities of raw materials such as blacksmithing, silicon metal, coal, until it begins to precipitate metallic copper.
A slow of the molten glass cooling cycle causes the separation of metallic copper from the base glass.
The homogeneity of the distribution of copper crystals characterizes the dell'avventurina quality.
The origin of the term avventurina takes its name from the definition given by the seventeenth-century glassmaker Giovanni Darduin:
"la si dimanda venturina, et con ragione, perché sortisse più per ventura che per scientia"
"It's named venturina, with reason, because it was the result of chances than science".
È definito "cristallo" il vetro incolore e trasparente, decolorato con biossido di manganese, ottenuto con materie prime depurate. Fin dai tempi del Medioevo il cristallo è considerato il più pregiato vetro muranese. Il segreto della sua qualità sta nelle purezza delle materie prime impiegate, nell'uso di decoloranti, nella preparazione della miscela vetrificabile e nella condotta della fusione. Nella metà del XV secolo i muranesi proposero un vetro puro e incolore, che per la prima volta nella storia venne chiamato cristallo e successivamente venne riprodotto in altri paesi europei. A differenza del cristallo nordico, che presenta una alta concentrazione di ossido di piombo e che oggi deve sottostare a severi controlli relativi ai fumi derivanti dalla fusione, il cristallo muranese è un vetro sodico-calcico i cui componenti principali, oltre alla silice, sono l'ossido di sodio e l'ossido di calcio. Il cristallo sodico risulta molto adatto alla produzione di oggetti soffiati particolarmente leggeri che richiedono lunghi tempi di lavorazione.
It is a glass obtained by heat decorative technique, invented in Murano in the first half of the sixteenth century.It involves the use of chopsticks containing smooth wires in "milky" or colored glass. If the wires in the rods are twisted, or spiral, the watermark is called "retortoli" while if the sticks are crossed the watermark is called "reticello" or "double".
Milk Glass "Lattimo"
Milk glass is an opaque white glass such as milk (hence the name), the invention is dated in 1450 in Murano in order to imitate Chinese porcelain arrived in Venice, using as matting of lead and tin mortar.
In the Renaissance, and in the eighteenth century milk glass it was used mainly for the production of refined blown objects, decorated with polychrome enamels.
In today's machining opacifying agents used are characterized by minute crystals of calcium and sodium fluoride are separated from the molten glass during cooling.
These crystals are all the more homogeneous the higher it is the concentration of zinc oxide in the mixture.
Similar to the milky, from the aesthetic point of view, is the enamel-based glass lead arsenate, used especially in the fabrication of the beads and of the watermark.
Blowing around the middle of the first century BC was a technique which revolutionized the glass production, making rapid and accessible the production of glass containers facilitating their widespread even at the most modest classes.
The origin of the swelling occurred in the Syrian-Palestine, initially did not exist a real cane breath but a vitreous hollow barrel which was closed at one end allowing the modeling in that area in the form of bottle, while in the other end She occurred blowing generated by the master glassmaker.
In a second time the modeled object was removed from the rest of the glass barrel.
The introduction of a metal rod made easier the work of the glassmaker and expanded the product range.
The "Sommerso" is a shape of the glass art of Murano which has layers of contrasting colors (usually two), the technique involves dipping a blown thick in the crucible containing the transparent glass of another color and equally wide thickness.
The superposition of transparent glassy thick allows to obtain special chromatic effects.
Undeclared was developed in Murano during the late thirties and was popularized in the fifties by Seguso Vetri d'Arte, directed by Flavio Poli.
This process is a popular technique for the vessels, and is sometimes used for the sculptures.