Glass

**What glass is?** It is a hard material normally fragile and transparent common in our daily life.

 -  Sand - Soda ash - Limestone
 * Components** 

**How it is produced?** By fusing these materials (sand, soda ash, limestone) at high temperatures, then cooling them quickly ,forming a enough time to form a crystalline regular structure.   - Solid and har material - Disordered and amorphous structure - Fragile and easily breakabbe into sharp pieces - Transparent to visible light - Inert and biologically inactive material
 * Properties**

**Types of glass**

- Comercial glass (soda lime glass) - lead glass: for decorating purposes - Borosilicate glass: for kitchen or chemial labs purposes.  And other uses: Safety glass, fiber glass, foam glass.

//**Glass Paragraph **//

Glass in Caracas is used principally in architecture, in the windows of buildings or as walls of the facades of buildings. Glass also is frequently used in the big doors of the entrances of buildings such as hotels, business centers and government buildings. In sites like churches glass is commonly used to make stained-glass windows. This material also is used in the roof of the shopping centers like sambil or the subway stations like “la Rinconada”. In these buildings are used opaque glasses that provide more privacy and give elegance. These glasses have different colors (black, blue, yellow, green, etc). This material is used in conjunction with other materials such as concrete or steel that provides a basis on which to be supported, because glass is a very fragile material, unable to withstand heavy loads. Although glass gives a modern character to the city of Caracas, the role that this plays in cities in other countries do not apply to Caracas because of our tropical climate, the sun's rays are reflected thanks the glass of the buildings and produce a greater warming in the soil and other structures within the city, which leads to an increase of global warming and a hot climate The use of glass is not very commonly in urban planning; only urban furniture and also roofs of bus stops or little details on de city. So glass is a material very used, more in architecture than urban planning. And in city of Caracas, glass is common used on the facades of office buildings and the windows of almost any building, but not is a material widely used in urban planning.

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