Ancient metallurgical furnaces maintained with the massive use of local charcoal wiped out vegetation and irreparably damaged a valley in southern present-day Israel 3,000 years ago.
Researchers from Tel Aviv University (TAU) collected samples of charcoal used as fuel for metallurgical furnaces in the Timna Valley, located in the desert region of southern Israel, during the 11th to 9th centuries BC. C. and examined them under a microscope.
They found that the coal fuels used changed over time. Early samples contained mainly local white brooms and prickly acacias, excellent fuel available nearby, but the quality of the firewood had deteriorated over time, and later samples consisted of low-quality firewood and wood imported from far away.
“Our findings indicate that the old copper industry in Timna was not managed sustainably, and the overexploitation of the local vegetation eventually led to the demise of both the plants and the industry. Copper production was not renewed in this region. until about a thousand years later, and the local environment has not fully recovered to this day,” say the researchers, whose study was published in Scientific Reports.
KING SOLOMON MINES
Professor Erez Ben-Yosef, director of the archaeological excavations in the Timna Valley, says: “Many finds in the Timna Valley indicate that a large copper industry flourished here over a period of about 250 years, between the 11th and 11th centuries. IX BC, with thousands of mining sites and about 10 processing sites that used furnaces to extract copper from ore.
“This impressive operation is known to the public as ‘King Solomon’s Mines’, and today we know that copper production peaked here at the time of Kings David and Solomon. The Bible never mentions the mines as such, but it does tell us that David conquered the region of Timna, then known as Edom, placing garrisons throughout the land, so that the Edomites became his subjects, and his son Solomon used large amounts of copper to build the Temple in Jerusalem.
“We can only assume that David took an interest in this remote desert region because of its copper, an important and valuable metal at the time, which was used to make bronze, among other purposes. The Timna copper industry was run by the Edomites locals, who specialized in this profession, and the Timna copper was exported to distant lands, including Egypt, Lebanon, and even Greece. This study shows, however, that the industry was not sustainable, a fact that may fit well with occupation by a foreign power, perhaps ruling from Jerusalem.”
The researchers explain that the Timna copper industry was very advanced for its time and that the blacksmiths who processed the copper were skilled and highly respected people. Copper was extracted from the ore by smelting in earthenware ovens at a temperature of 1,200 degrees Celsius. The whole process took around eight hours, after which the furnace was broken and the copper was recovered from its base. The charcoal necessary to reach the high temperature was previously manufactured in special sites, by slow combustion of trees and bushes felled for this purpose.
“The copper industry in Timna was first discovered about 200 years ago, and since then every researcher who visited the area has asked the same question: What fuel was used to heat the smelting furnaces? Since the vegetation is very sparse in this desert area, where did the firewood come from? To finally solve this mystery, we collected charcoal samples from smelter sites and examined them in the lab,” explains co-author Mark Cavanagh.
The charcoal samples, well preserved thanks to the dry desert climate, were taken from industrial waste heaps at two large production sites in the Timna Valley and brought to the TAU Archaeobotany Laboratory.