From the jar that holds the morning marmalade, the mirror in which we brush our teeth, the windows and car windscreen we look through, the computer screen many of us look at every day to the light bulb we switch off last thing at night; glass is around us everyday.

Glass is a combination of sand and other chemicals that are melted together at very high temperatures to form a material that is ideal for a wide range of uses from packaging and construction to fibre optics. People probably first realised glass was possible when they saw melted sand in the bottom of a fire. Among the earliest users of glass were the ancient Egyptians. They made glass bottles as early as 2000 b.c. These were found in the tombs of the pharaohs. About a thousand years later, the Chinese were making coloured glass into imitation gemstones.

A form of glass occurs naturally within the mouth of a volcano when the intense heat of an eruption melts sand to form obsidian. Man first used this as tips for spears.

Today we have mastered the glass making process and can make many different types of glass in many different colours and for many different uses.

Glass is made by melting together several minerals at very high temperatures. Silica in the form of sand is the main mineral and this is combined with soda ash and melted in a furnace at temperatures of 1700oC. Other chemicals are also added to produce different colours or properties.

Whilst it is still molten the glass is manipulated to form packaging, car windscreens, glazing or numerous other products. Depending on the end use, the composition of the glass and the rate at which it is allowed to cool will vary, as these two factors are crucial in obtaining the properties the glassmaker is seeking to achieve.

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