History of glass

The history of glass-making goes back more than 3,600 years ago, starting in Mesopotamia. Some believe people were making glass-like objects even earlier in Egypt. At first, glass objects such as beads might have been made by accident during metal-working or while making a material called faience. For a long time, glass was very rare and only the wealthy could afford it.

Later, glass technology developed in places like India. Many glass items from the time of the Roman Empire have been found. These were used in homes, for work, and even in special places for remembering people who had passed away. In Anglo-Saxon England, people made many things from glass, such as cups, beads, windows, and even pieces of jewellery.

Origins

Naturally occurring glass, like obsidian, was used by many early societies to make sharp tools and was traded widely. The first true glass was likely made along the coasts of north Syria, Mesopotamia, or ancient Egypt.

A piece of glass found in Eridu, Iraq, dates back to the twenty-first century BCE or earlier. It was made during the Akkadian Empire or the early Ur III period and was blue, achieved using cobalt. This type of glass is known as Egyptian blue, though the technique was used in Eridu before it appeared in Egypt.

Because Egypt’s dry climate helped preserve items well, most early glass studies come from there, though some may have been imported. The oldest known glass objects, from the mid-third millennium BCE, were small beads. These may have been made by accident during metal-working or while making a material called faience.

During the Late Bronze Age in Egypt and Western Asia, glass-making grew quickly. Finds from this time include colored glass pieces, vessels shaped like valuable stones, and many beads. The glass from Syria and Egypt used soda ash, made from plant ashes.

By the 15th century BCE, glass production was common in Western Asia, Crete, and Egypt. The Mycenaean Greek word for glass workers has been found written in Linear b script.

Glass stayed a luxury item. After events that affected Late Bronze Age cultures, glass-making slowed but restarted in Syria and Cyprus by the 9th century BCE, when ways to make colorless glass were found.

The oldest known guide to making glass comes from about 650 BCE, found in tablets in the library of the Assyrian king Ashurbanipal.

In Egypt, glass-making restarted later, in Ptolemaic Alexandria. New methods were tried, and glass was used for bigger items like tableware. Techniques such as shaping soft glass over a mould and creating patterns with colored glass strips were developed.

According to the writer Pliny the Elder, Phoenician traders may have first discovered glass by accident. A story says that when merchants used blocks of nitrum as supports for their cooking pots on the beach, the nitrum mixed with sand and created glass.

During the 1st century BCE, the method of glass blowing was invented on the Syro-Judean coast, changing glass-making forever. This made glass vessels much cheaper than pottery. Glass use grew across the Roman world. Glass became like plastic to the Romans, and glass made in Alexandria spread through the Roman Empire. Clear glass was made around 100 CE in Alexandria, leading to the use of glass for windows in important Roman buildings and luxurious homes in Herculaneum and Pompeii. Over the next thousand years, glass-making continued to develop and spread through southern Europe and beyond.

History by culture

Iran

The earliest Persian glass beads date back to 1600 BCE and were found in Iran. Glass tubes from the middle Elamite period were discovered in Chogha Zanbil. Mosaic glass cups from northern Iran resemble those from Mesopotamia.

Levant and Anatolia

A glassmaking crucible from 2011–2014 excavations in Turkey is the oldest evidence of glassmaking in the Syro-Levantine zone. This discovery is slightly earlier than glassmaking evidence from Egypt. The fragment may be linked to the Kingdom of Mitanni and could be connected to glassmaking descriptions in cuneiform tablets. A glass bottle fragment from central Turkey around 1600 BC might be the oldest glass in Anatolia.

India

Glass evidence from the Chalcolithic period was found in Hastinapur. The earliest glass item in the Indus Valley civilization is a brown glass bead from Harappa dating to 1700 BCE. Texts like the Shatapatha Brahmana and Vinaya Pitaka mention glass, suggesting its presence in early first millennium BCE India. Widespread glass use began in the 3rd century BCE in Taxila. Kopia in Uttar Pradesh is the first site in India to locally manufacture glass, dating between the 7th century BCE and the 2nd century CE. By the 1st century AD, glass was used for ornaments and casing in South Asia. Contact with the Greco-Roman world introduced new techniques.

China

Glass played a smaller role in China compared to ceramics and metalwork. The earliest glass items in China come from the Warring States period (475–221 BCE). Glassmaking developed later in China than in Mesopotamia, Egypt, and India. Imported glass objects first reached China during the late Spring and Autumn period (early 5th century BCE). During the Han Dynasty (206 BCE–220 CE), glass use diversified with the introduction of glass casting for objects like bi disks. Chinese glass from this period contains high levels of barium oxide and lead.

Roman World

Roman glass production grew from Hellenistic traditions, focusing on colored, cast glass vessels. Glass objects were found across the Roman Empire in various contexts. By the 1st century CE, techniques advanced with glass-blowing and the rise of colorless or ‘aqua’ glasses. Raw glass was produced separately from vessel working, and large-scale manufacturing in Alexandria established glass as a common material.

Islamic world

Islamic glass built on pre-Islamic cultures, especially Sasanian glass. The Arab poet al-Buhturi praised the clarity of such glass. In the 8th century, the Persian-Arab chemist Jābir ibn Hayyān described recipes for colored glass. By the 11th century, clear glass mirrors were produced in Islamic Spain.

Africa

Evidence suggests indigenous glass production existed in West Africa before extensive contact with other regions. The Ife Empire in Southwestern Nigeria produced glass beads, crucibles, and debris from the 11th to 15th centuries CE. Chemical analysis showed unique compositions, reflecting local materials. Colors were created using manganese, iron, cobalt, and copper.

Medieval Europe

After the Western Roman Empire fell, Northern Europe developed independent glassmaking. Byzantine Glass continued Roman traditions in the Eastern Empire. The claw beaker was a popular vessel. Glass objects from the 7th and 8th centuries were found on Torcello near Venice. Around 1000 AD, Northern Europe shifted from soda glass to potash glass from wood ashes. Stained glass became important in Romanesque and Gothic art, mainly in churches.

Anglo-Saxon world

Anglo-Saxon glass was used for vessels, beads, windows, and jewelry. After the Roman departure from Britain in the 5th century AD, glass use changed. Most complete vessels and bead assemblages come from early Anglo-Saxon cemeteries. From the late 7th century, window glass became more common with the introduction of Christianity and church construction.

Murano

Murano became the center of luxury Italian glassmaking from the 14th century, developing new techniques and exporting dinnerware, mirrors, and other items. The Venetian Republic moved glassmakers to Murano in 1291 to prevent fires. Murano glassmakers became prominent citizens, and many later set up furnaces in other cities.

Bohemia

Bohemian glass, or Bohemia crystal, has been produced since the 13th century in regions now in the Czech Republic. Notable sites include Skalice, Kamenický Šenov, and Nový Bor. The style excelled in Baroque glass from 1685 to 1750. In the 17th century, Caspar Lehmann adapted gem engraving techniques to glass using copper and bronze wheels.

Modern glass production

New processes

A big step forward in making glass was adding lead oxide to the hot glass. This made the glass look better and easier to shape. This method was first discovered by George Ravenscroft in 1674, who made clear lead crystal glass on a big scale. Ravenscroft used flint as a silica source, but his glass sometimes cracked. He fixed this by adding lead oxide.

By 1696, many glass factories in England were making this type of glass and selling it across Europe. In 1746, the British Government put a high tax on it. Glass makers responded by making smaller, more detailed pieces. The tax was removed in 1845, and the glass industry grew.

Evidence shows that the blown plate glass method was used in London in 1620 for mirrors and coach plates. In 1688 in France, a new way to make very large glass plates was developed. This method was later used in England in 1773 at Ravenhead. The polishing process became automated around 1800.

Industrial production

Glass became popular as a building material after The Crystal Palace was built in 1851 for the Great Exhibition. In 1832, a British company started using the cylinder method to make sheet glass. This involved blowing glass into long tubes, cutting them, and flattening them.

In 1847, a new method called the Rolled Plate method was introduced, which gave glass a ribbed finish. It was often used for large glass roofs, like in railway stations.

In 1887, a company in Castleford, Yorkshire developed a way to make glass bottles faster. In 1888, a method for making patterned glass was introduced.

In 1898, a strong type of glass with wire mesh was invented, often called "Georgian Wired Glass." In 1910, a new way to draw window glass was invented in the US.

In 1938, a better way to make polished glass plates was developed. Between 1953 and 1957, a new method called the float glass process was created. This method uses a bath of molten tin to make very flat glass sheets. This is how most modern windows are made.