Glass is as old as lightening and sand. I would love to walk the beach and find a Fulgurite. The sometimes hollow tube of fused sand, if small, would make a lovely necklace after wrapping with silver wire. Often the lightening glass is too large and appears in the shape of the lightening itself as you can see here.
Another form of natural glass is Obsidian. It is considered a rock and has been used for arrowheads, knives, and cutting tools. Obsidian is created by the volcanic heating of sand and rock.
Man produces glass by combining sand, soda ash and limestone then heating to a temperature of 1700 degrees. The liquid is then poured into a form or float and cooled to give us a variety of uses. The rich history of glass use has come from Ancient Egypt, Rome, China, England, France, Italy and more recently the United States.
In the past people used small inefficient furnaces, whereas today you can purchase a large industrial size furnaces or one as small as a kiln. Early glass creations were of glass covered clay pots, jewelry, jugs and jars. Later came transparent glass, glass blowing, painting and gilding. In 1674 George Ravenscroft patented lead glass. This type of glass contains lead oxide used for optical instruments.
The cost of glass initially made it unattainable for most. Manufacturing and uses have expanded in the modern age and prices are affordable. Now we use glass for optical fibers in laser communication, glass containers that can safely store radioactive waste, cookware and even lenses for night vision goggles. Glass is widely recycled and does not lose its integrity no matter how many times it is reheated.
Photo by Robert Magorien/Dreamstime