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Glass is an amorphous (non-crystalline) solid material. Glasses are typically brittle and optically transparent. The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, made of about 75% silica (SiO2) plusNa2O, CaO, and several minor additives. Often, the term glass is used in a restricted sense to refer to this specific use. In science, however, the term glass is usually defined in a much wider sense, including every solid that possesses a non-crystalline (i.e.,amorphous) structure and that exhibits a glass transition when heated towards the liquid state. In this wider sense, glasses can be made of quite different classes of materials: metallic alloys, ionic melts, aqueous solutions, molecular liquids, and polymers. For many applications (bottles, eyewear) polymer glasses (acrylic glass, polycarbonate, polyethylene terephthalate) are a lighter alternative to traditional silica glasses. Glass, as a substance, plays an essential role in science and industry. Its chemical, physical, and in particular optical properties make it suitable for applications such as flat glass, container glass, optics and optoelectronics material, laboratory equipment, thermal insulator (glass wool), reinforcement materials (glass-reinforced plastic, glass fiber reinforced concrete), and glass art (art glass, studio glass).

Glass History
From the start of time glass has been available to man. Stone Age man used obsidian (a naturally formed glass) for cutting tools and weapons.

The Phoenicians also accidentally discovered glass when cooking near nitrates that when heated formed glass. However, we have to wait until Egyptian times before we can actually trace deliberate glass manufacture which was in the form of beads. In 1500bc, we believe the first glass bottles were made using the "Core-Forming Method". As far as the early history of glass making in Britain goes, the Romans brought the technology with them. This led to the European-wide spread of glass manufacture. British history records glass "Manufacture" dating back to the 13th century when "Broad Sheet" glass can be located to the areas around Sussex and Surrey. In the meantime the Venetians had thrived as glassmakers, as their glass became popular due to its brilliance and creative form. By 1330 the French had also developed "Crown Glass". This took until the 17th century to be produced in England, in London. In England in 1676 George Ravenscroft invented "Lead crystal" by introducing lead oxide to the glass which took on a more brilliant appearance. The 17th century brought a new glass process from France, "Plate glass", a term still used today. This was a process of pouring molten glass onto a table and then rolled. Once cold, the glass was ground under large grinding discs until optically smooth, making it perfect for mirrors. The French had legislated heavy duties on imported glass products which made it impossible for the Venetians to Export, and also offered generous incentives to any Venetian willing to work for them. By the 18th century this technology was being used in England at Ravenhead, producing the first English Polished Plate. 1834, Robert Lucas Chance introduced "Improved Cylinder Sheet" glass which was produced using a process invented in Germany. This produced even finer and larger glasses. This was the glass used to glaze the "Crystal Palace" in London. Until a change in legislation in 1845 when the "Excise Act" was repealed, glass manufacture was under developed in Britain. Once the heavy tax burdens previously placed on glass manufacture were removed, production grew.

By the end of the 19th century glass bottles were being made by machine, increasing production threefold. The now "Chance Bros." invented "Machine rolled patterned glass". By the start of the 20th century, "Owens Glass" in America had further developed bottle manufacture which increased output by 10-fold to some 2,500 bottles per hour. By 1910 the first "Laminates" had been produced by Edouard Benedictus, a Frenchman, who named his process "TripleX." 1914 saw the start of producing glass by the "Drawn" method. Invented by a Belgian man named Fourcault, glass was drawn vertically from a tank. A further development by Bicheroux, another Belgian, was to pour the molted glass from a pot between 2 rollers to give a more even thickness and evenness for polishing. In 1917 "Sheet glass" was invented by Colburn in America, and developed by "Libbey-Owens", a partnership of Michael Owens of Owens glass and his backer E. D. L. Libbey. Further improvements were made by "Pittsburg Plate Glass" or PPG. By 1923 came the first UK production of continuous polished plate glass using the single grinding system. Closely followed in 1938 by the twin grinding system. And then the float process was launched in the market place; invented by Pilkington Bros. and introduced in 1959. The significance of this process is that it produced glass with a brilliant finish and without the need to grind or polish the surface, making mass-produced glass with the qualities of polished glass. This was achieved by floating the molten glass on a bath of molten tin, creating a "glass ribbon", even in width and thickness. This is still the process used today for the production of what is now termed "Float Glass".

Recycling Glass, its not just about saving the planet
Due to our increasing success, Specialist Glass products Ltd use a LOT of glass. This also means we generate a lot of broken glass as any one who knows anything about curving and processing glass would know. As a responsible business, we aim to recycle as much glass as possible as the benefits of doing this are enjoyed by more than just our business. Did you know that glass recycling requires 30% less energy to melt when compared to virgin raw materials? Less energy means less fuel burnt and so less emissions. Every tonne of glass recycled is one tonne less that goes into landfill therefore saving our countryside. It's not only business that can make a difference. Around 8% of household rubbish is glass and as of 2003, 1.4 million tones of it were stored into landfill. The cost of getting it collected and sent to landfill is £65 per tonne of glass, which amounted to £93 million of council tax. 2003 estimates show that if all glass were collected and recycled the UK could create nearly 8000 new jobs. So your empty marmalade jar could help save the planet and the economy instead of taking up space in your bin. Recycling process The collected glass is crushed and sorted to remove bottle lids and other contaminants. Lasers, magnets, the human eye and even digital cameras are used to remove these. To use the proper industry term, the cullet is then added with raw materials and put into a furnace to be pressed or blown into shape. Glass recycling facts Recycled glass has the same level of quality as that made from virgin raw materials, no matter how many times it is recycled. With over 50,000 glass-recycling banks around the UK, you can be sure there is one near you for you to put the 331 bottles and jars your average household generates. To put this into perspective, for every bottle you recycle, the energy saved is equivalent to a 60-watt bulb being switched on for almost 2 hours or a television for 20 minutes. When compared to the rest of Europe, the UK is behind when it comes to recycling glass. This could be attributed to less glass collection points made available or the tougher approach of local authorities in Europe e.g. refusing to take rubbish with recyclable material in it.

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