Glass is everywhere in the 21st century, and the uses for the material are becoming more and more creative, year on year. Specifically, this is the history of glass production, looking at when glass was invented, natural glass and more. Let’s take a look at the remarkable journey the glass in your window frames has taken over the last 5,000 years.
From waking up in the morning, and looking at your watch or your phone, to looking out of the window at the weather outside, to defrosting your icy car windscreen on a cold winter morning, to spending all day at work fixed intently on computer monitors, laptops and tablets, to spending your evening watching your favourite shows on the television. For many of us glass is always in our eye line – even if we don’t wear glasses.
It’s therefore quite difficult to believe that glass begins as a material many of us wish we were closer to on a more regular basis – sand. Glass was ‘invented’ from melting a quantity of sand. However, nowadays this is rarely a naturally occurring phenomenon as the sand requires a heat of at least 1700 °C (3090°F) to undergo glassification (the process by which sand turns into glass). It therefore took many, many years of human evolution before we had the tools required to make advancements in glass. Let’s take a look at the history of glass production…
THE HISTORY OF GLASS PRODUCTION: NATURAL GLASS
In times gone, of a more unstable Earth mantle, volcanic eruptions were less rare than they are in the present day. This meant that, in these times, the natural glass compound, Obsidian, would have been produced more regularly. Obsidian is a volcanic glass, created from molten lava. When molten lava containing large amounts of silica sand, cools quickly after reaching the Earth’s surface, Obsidian forms. This usually occurs when the molten lava comes in to contact with water, causing heat energy to rapidly vacate the molten lava into the surrounding area. This rapid cooling prevents the atoms arranging into a crystalline structure in the now hardened material, leaving a brittle, amorphous, and useful, material in Obsidian glass.
Obsidian was used by early man in the form of arrow heads and daggers, and is still used in the modern day in surgical scalpel blades! Another way glass can form in nature is when lightening strikes silica sand, usually in a desert or beach biome. This creates the rare natural glass – Fulgurite.
THE HISTORY OF GLASS PRODUCTION: MAN-MADE GLASS
Now, let’s look at when glass was invented by man. Interestingly, According to archaeological findings, the first man-made glass came from around 3500BC, in the form of glass beads found in Egypt. For the first few thousand years, the glass production process was painfully slow and often very hit and miss. Until Syria produced the ‘blowpipe in 1st century BC – something that revolutionised glass production.
For nearly 2000 years the art of ‘glassblowing’ was the go to method of glass production in the western world. Glassblowing involves rotating the blowpipe over the molten glass, whilst in the furnace, causing the sticky glass to anneal to the instrument. The molten glass and blowpipe are then moved to a small steel table, known as a ‘marver’, where the glass is rolled in order to evenly distribute heat. From this point the glassblower will take deep breaths down the blow pipe, with the goal of creating air bubbles in the glass, causing the shape and size of the glass to distort and change. The glass would be oscillated during this process in order to create an even finish.https://www.youtube.com/embed/dtxrtKd-Vao?feature=oembedSome Glassblowing in action! (Video from ‘Novica’ on Youtube)
Even at this point though, the main purpose glass was being used for was for carrying water, and simply for decoration. Interestingly, It’s only relatively recently that people have started to take notice of the insulating properties of glass.
MODERN ERA GLASS WINDOWS
Glass first became common in household window frames in the 17th century. Prior to this, people used a variety of materials, including: marble, animal hide, cloth and slate. Interestingly, the introduction of glass windows into households across the western world coincided with a large downturn in disease spreading, and ultimately led to people living a more disease-free lifestyle!
However, methods for creating uniform glass sheets, at specific measurements, were basic and inconsistent. That was until the 1950’s when glass manufacturer Pilkington came up with the “float glass process”. This, subsequently, became a key moment in the history of glass production. The float glass process consists of a sheet of molten glass floating as a contained unit on a bed of molten metal, which can be lead, tin or another metal alloy. This revolutionary glass making process allows the creation of uniform glass sheets that are of a consistent depth across the whole area. Modern day glass manufactureres still use the float glass process today!
Nowadays, there are a variety of different glass types you can choose to inhabit your window frames. For example, you can now choose from a whole host of variations, including: lead-based glass, tempered glass, soda-lime glass, annealed glass, stained glass, tinted glass, safety glass, laminated glass and more.
Another large advancement in window technology is Double-Glazing. Double-Glazing was, rather aptly, invented in Scotland. Where, at certain times of the year, it’s insulating properties are very much welcome. Interestingly though, Double-Glazing first became big in America, in the 1950s, before the UK followed suit in the 70s and 80s. These days, Double-Glazing comes as a hugely variable product. Obviously the customer can choose the size of a Doubled-Glazed unit, but not only this: The outer glass, inner glass, spacer bar colour, spacer bar width, the gas it’s filled with, are all options a prospective buyer can customise.
As a glass manufacturer, we could discuss Double-Glazing until the cows come home, but it would be remiss of us not to mention some of the other amazing things glass is being used for in the modern day…
GLASS: THE MATERIAL OF MODERNITY
We are in a remarkable era along the timeline of the future history of glass production. An incredible feat of glass engineering that 64% of us take for granted, is an invention that cheats evolution, in a way only matched by advancements in medicine – glasses. Glasses, specifically lenses, consist of varying thicknesses of curved glass that direct light into the retina, in those where the eyes themselves have become less efficient at the task. Thus, allowing the individual to be able to see. Interestingly, there are various accounts of when this glass was invented, with some dating back to the 17th century and some not until the early 1900s.
A common theme of great glass inventions, seems to be that we largely take them for granted. Remember the days of dial-up internet? Even the days when everything ran through electrical cables were rather hit and miss. Everything changed with fibre optics. Fibre optics work through the use of thin glass fibres that reflect light from point A to point B, within a casing. In addition, Optical fibre glass was invented in the 1970s, and connection speeds have been revolutionised in the western world ever since.
Smartphone screens are a more recent manipulation of glass, that has proven to even more popular that glasses! With over 85% of the British population owning a smartphone in 2019. Smartphone screens tend to be made of a material called ‘aluminosilicate glass’, which is thin enough to allow the screen to be interactive, and tough enough to resist scratches and shattering. To expand, this glass was invented in 2007, under the brand name: ‘Gorilla Glass’.
As you can see we are currently in one of the most exciting periods in the history of glass production! Incredibly, one day we’ll probably look back on this era in the history of glass production as old fashioned – when undoubtedly, there’ll be newer and more outlandish glass technologies available.
THE HISTORY OF GLASS PRODUCTION: CONCLUSION
Thank you for joining us on a look at the history of glass production! In conclusion, glass is one of, if not the sole, greatest material we have on planet earth. Whether it be natural, or man-made, glass has always been an ally to the human race, and will continue to be that very thing, well into the future. When you think of the future, what do you picture? Glass. Subsequently, at Clayton Glass, we can’t wait for what comes next in the evolution of glass. Finally, thank you for reading about the history of glass production.