Glasses..

There are several kinds of glasses that can be adapted to different uses. Glass can be manipulated to form packaging, car windscreens, glazing or numerous other products. Bottle-glass is the coarsest and cheapest kind of glass which consists of alkaline earth and oxide of iron combined with alumina and silica. While, the best and most beautiful are the flint and the plateglass. They are composed of fixed alkali, pure siliceous sand, calcined flints and litharge, in different proportions.
Glass is made by melting together several minerals at very high temperatures. Silica in the form of sand is the main ingredient and this is combined with soda ash and limestone. Other materials can be added to produce different colours or properties. These materials for making glass must first be reduced to powder, which is done in mortars or by horse mills. After having a powder, sift out coarse parts and mix silex and flux together, put in furnace, and heat for five to six hours, stirring it often during this process. Once done the material is taken out and is called frit. It is then easily converted to glass by pounding it out and vitrifying it in a melting pot. This is the state when different color can be added. Then, blow the glass to form different shapes and make different things and the whole glass making process is done.

Licha Permata Amanda
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