Mummy had a tough time pleading with 3-year-old Ria to drink her 'nimbu pani' in her baby mug. Ria wanted it in the same glittering crystal glass grown-ups drink from. Actually, Ria is hardly to be blamed. Glass has a mystic beauty that fascinates all, young and old.

Have you ever wondered where glass comes from? Today, all the glass we see around us is manufactured in factories. We take glass for granted, but few people are aware of its origins.

History and origin

The precise origin of glass is not known. Narrations in historical documents however show that natural glass was discovered by man perhaps as early as the Stone Age. Manmade glass came into the picture much later.

According to the writings of the Roman historian Pliny (AD-23-79), Phoenician merchants who traded soda, undertook long voyages to carry on the trade. On their way they would spread out on seashores to prepare their meals, and lit fires on the sands. The problem was that on vast empty shores of the beach they could not find anything to support their cooking pots over the fire. Therefore they used lumps of soda.

One such time, as the fire grew stronger, streams of liquid started flowing around the fire. The soda had combined with the sands, which melted in the intense heat and formed a curious liquid. As the fires died, the liquid solidified to form a transparent material. This was glass.

The basic raw materials of glass, silica i.e. sand and soda, were thus discovered around 5000 B.C. Man now knew that glass is nothing but sand, melted and then cooled.

This may seem confusing because we have seen that when solids melt to form liquids, on cooling, they generally return to their original state, like wax. Not so in the case of sand. Sand molecules rearrange themselves in a new fashion once they are melted and cooled, giving us continuous transparent medium or glass.

These merchants spread this knowledge along the Mediterranean coast and a new craft, that of glass making, was born.

Glass as found in nature

In nature, glass was discovered perhaps during volcanic eruptions, when certain types of rocks melted and then, cooled and solidified very rapidly. This was presumably the first known form of glass. It was called 'obsidian' and was used to make cutting tools like spears knives etc. by the people of that age.

Other violent natural phenomena (associated with high temperatures) like lightning strikes into sand dunes, melted sand and produced glass. The glass from these sources was called 'fulgerite'. Other names such as hyalopsite, Iceland agate, mountain mahogany and obsidianites were also prevalent.

These naturally occurring forms of glass are no longer of any significance.