1,600-yr-old kilns said to show Israel was world center of glass manufacturing

Archeologists said Monday they have discovered the remains of the oldest kilns known in Israel, where commercial quantities of glass were produced and later marketed throughout the Roman Empire.

The Israel Antiquities Authority said in a statement that two 1,600-year-old kilns were unearthed at the foot of Mount Carmel, off the country's northern Mediterranean shore, in salvage excavation ahead of the construction of a new railroad.

The discovery stirred excitement among the international community of glass researchers, the statement said.

"This is a sensational discovery and it is of great significance for understanding the entire system of the glass trade in antiquity," said Professor Ian Freestone of the University College London, an expert on the chemistry of early materials, was quoted as saying.

He said the discovery suggests Israel was "a production center on an international scale," manufacturing glassware that was widely distributed throughout the Mediterranean and Europe.

According to Abdel al-Salam Sa'id, the excavation director, the kilns were made of two compartments: a firebox for creating high temperature and a melting chamber. Clean beach sand and salt, the raw materials of glass, were inserted and melted together at a temperature of about 1,200 degrees Celsius (about 2,192 degrees Fahrenheit.)

The mixture was heated for a week or two until enormous chunks of raw glass were produced, some of which weighed more than 10 tons. At the end of the manufacturing process the kilns were cooled; the chunks were broken into smaller pieces and sold to workshops where they were melted again to produce glassware, the Antiquities Authority statement quoted Sa'id as saying.

Archeologists say that there were two main types of glass in the ancient world: Alexandrian glass from Egypt's Alexandria, and the so-called Judean glass, a cheaper, light green glass from the Land of Israel.

Remains of the Judean glass were found throughout the Roman Empire. Chemical analyses of ancient glass vessels discovered in Europe and in shipwrecks in the Mediterranean Basin have traced the origins of the glass to the northern Land of Israel. But the ovens where this glass was manufactured were never found.

"The current discovery completes the missing link in the research and indicates the location where the famous Judean glass was produced," the Antiquities Authority said.

During the Early Roman period, the use of glass greatly expanded due to its transparency, beauty, the delicacy of the vessels and the speed with which they could be produced by blowing -- an inexpensive technique adopted at the time that lowered production costs.

"Glass was used in almost every household from the Roman period onward, and it was also utilized in the construction of public buildings in the form of windows, mosaics and lighting fixtures," the Antiquities Authority said.

Consequently, large quantities of raw glass were required which were prepared on an industrial scale in specialized centers, like the two recently-found kilns. Endit