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Curiosities about the glass

What is the difference between crystal and glass?

Crystal and glass is called to the same material, however, a fundamental difference between the two: While the glass is found in nature in different ways (for example, quartz or rock crystal), glass is the result the merger of certain materials (silica, soda and lime). However, there are windows created by nature, like obsidian, which is generated by the heat generated inside the volcanoes. By mistake, we refer to as lead crystal glass or optical glass, its transparency as glass emulates the natural rock, this resemblance has always constituted the main goal of the glassmakers at the time of producing their goods.

Who invented glass?

Glass was discovered by the Egyptians in about 3000 BC .


How and why is the glass?

The glass comes from the high temperature fusion of a mixture of silica sand, calcium carbonate and sodium carbonate in a furnace. The point at which the mixture glass passes from solid to viscous liquid between 1300 and 1500 degrees Celsius. Subsequently and gradually returns to a solid consistency through a slow cooling process, until finally reaching its characteristic appearance of transparent solid material.

What is the natural color of glass? How do I provide color?

The natural look of the glass is colorless. However, due to high iron content found in deposits of silica sand, the color glass is generally acquired a greenish hue. During the manufacture of glass are added various metal oxides to provide color. For example, the blue glass is due to cobalt oxide. The tone coffee, nickel oxide. And for some shades of yellow glass using iron oxide.


How do you make the "cut glass"?

The "cut glass" (itself: the lead glass cut) is one of several techniques exist to decorate the glass. This technique is applied to the part already finished, ie it is a technical working cold. First, draw the glass surface, then the courts are run by diamond wheel and finally polished.


What virtues presents the material to manufacture glass containers for pharmaceutical use?

Due to her condition of inert material, the glass appears as a very hygienic material and there is no chemical reaction with the contents thereof, protecting them from pollution and / or alteration.


Does the use of glass brings environmental benefits?

The glass is a 100% recyclable: life is infinite.


Why should the existence of glass more or less resistant to temperature changes of heat or cold?

It is due to variations in the formula and the difference in coefficient of expansion (expansion coefficient called the measure that defines the degree of expansion or contraction of a material undergoes when exposed to cold or heat). This means that: a lower coefficient of expansion, the greater the resistance to sudden temperature change.



What are the different types of glass?

The glass is classified based on the chemical components that are added during manufacture. Therefore, typed as lime glass, borosilicate glass and optical glass or lead crystal.


What is the glass cup?

Lime glass is ordinary glass. It consists dominantly of silica, as well as calcium and sodium. Lime glass is used for the manufacture of glasses, plates, vases and various appliances. Today its production is markedly improved, and added to it at a higher amount of silica, experience superior resistance to thermal shock. Thus, many objects made of glass actusalmente easily resist the containment of liquids hot, cold and better able to withstand impacts.


What is borosilicate glass?

It is a kind of glass that has a very low coefficient of expansion, so it resists thermal shock caused by temperature changes. Currently, this type of glass used as laboratory equipment and in the development of cookware called refractory.


What is the difference between tempered glass and safety glass?

- Tempered glass is glass that has a resistance limestone five times higher than normal because its cooling process is longer and more controlled. This makes the break is not divided into sharp fragments, but hundreds of small pieces of harmlessness.

- Safety glass, which may or may not be tuned, is produced primarily for automotive use. To manufacture must be placed between two glass sheet of polyvinyl butyral (PVB) or resin plastic, it is used to prevent, if hit, the small glass fragments were scattered, and, conversely, to remain attached to the plastic screen.


How do you make blown glass?

For the process of blowing glass must be a hollow iron rod tongs glazier. First, the cane is introduced into the mass of glass melting. When removing the rod, turn on a rock to give the initial form, and then blows up cause the bubble to leave the room you plan to develop. Later, with the pliers and some Puntila, begin to provide it with the desired shape, blowing and pushing the piece to achieve the desired result. Finally, it enters the annealing oven.


How is the leaded stained glass?

He made a drawing on paper and templates are removed from it. Then, the sectioned drawing or design previously developed, thanks to the templates is done to cut identical sheets of flat glass. Then cut pieces of glass can be decorated with enamel and eventually merge with a strip of lead called fescue.


What is sheet glass to the flame?

This is a type of glass works by using a blowtorch. With the flame of it is reached to soften the glass and thereby stretching is done, merge it, shape it and blow.


What is the silvered glass?

It is a glass treated with silver nitrate to give the appearance of a mirror. Formerly, this technique was used in order to resemble precious metals like gold or silver.