All About Glass
Discovered by the Mesopotamians around 3500 BC, the human race has used glass in many different ways. Here is everything you need to know about glass:
According to the Corning Museum of Glass, historians can trace evidence of manufacture and use of glass to communities living in Mesopotamia before 2000 BC. Others peg this period around 3500 BC. However, it is possible human ancestors used obsidian as glass 9,000 years ago. By 1500 BC, the Phoenicians and the Egyptians were proficient enough in the art of glass making to produce glass-based items, such as glass beads. During this period, glass was mostly a luxury material only accessible to the rich, noble or titled community members.
Bronze Age to first Century BC
Rapid breakthroughs in glass making technology did not occur until the Bronze Age. As a result, this industry went through cyclical boom and bust periods through 500 BC. Nevertheless, experimentation led to the perfection of certain techniques, such as making colored glass ingots. A common characteristic of glass objects from this period is color diversity due to high impurity content in raw materials. Colorless glass did not appear until the first century BC. Also, around first century BC, industry experts figured out how to color glass by adding certain colorants.
First Century BC Onwards
From Mesopotamia, glass making artistry spread to communities in the Mediterranean, Indian subcontinent, China and the western parts of Asia. The Chinese learned this technology from Mesopotamians and exported it to their land. The Romans are credited with introducing glass-making technology to Western Europe, including present-day England, France, and Germany. They also invented clear glass manufacturing via the addition of manganese oxide. Through the 11th and 13th centuries, Venetian artisans experimented with ways of making glass sheets and stained glass windows. In 1674, an English glassmaker pioneered and patented the use of lead crystal technology to produce glass with a high refractive index.
Other innovations along the way included:
• The introduction of “polished plate” in France in 1688
• Otto Schott’s study of various chemical element effects on glass optics and thermal properties
• Invention of tank furnace by Friedrich Siemens
• Invention of automatic glass blower by Michael Owens in the late 19th century
• Introduction of the gob feeder to industrial glass production lines in 1923, introduction of “Individual Section” machines in 1925
• Improvement of Pittsburgh process in 1928
• Float glass invention by Sir Alistair Pilkington (UK) in 1959
• The discovery of fluoride glass in France by Marcel and Michael Poulain and Jacques Lucas in 1984.
The Glass Making Process
To make a glass item/vessel, one needs various chemicals including sodium carbonate, pure silica, lime, aluminum oxide, magnesium oxide, sodium sulfate, antimony oxide, sodium chloride, boron oxide, iron, and cerium oxide. The glass making process has not changed much since the Bronze Age and Anglo-Saxon era. In essence, the process involves heating silica, soda ash, and lime to extreme temperatures. As this mixture cools down, it is shaped into various glass products via blowing or pouring into molds. However, some modern processes are highly automated. Moreover, manufacturers now routinely use additives to enhance color, durability and opacity of glass, among other desirable properties.
Common Uses of Glass
Glass material has almost limitless uses including:
• In building construction, glass abounds in fixtures including doors, windows, walls, roof light clearings, balustrades, tables and shelves
• Packaging of food and cosmetic products
• Manufacture of tableware including plates, cups, and bowls
• Manufacture of medical technology devices used in radiology, biotechnology, and optometrics
• In Automotive and transport industry to manufacture of vehicle windscreens, lights, and other structural components
• In fiber optic cables to relay information to and from PCs, TVs, and mobile devices
• Building construction: Buildings constructed entirely from glass and structural support beams are a common sight in many parts of the world now
• Manufacture of renewable energy appliances such as solar panels
Humans have found different ways to use glass since its discovery around 3500 BC. Today, glass is widely used in myriad industries including building construction, food packaging, automobile, solar panel and fiber optic cable manufacturing industries, among others.