Ceramic kilns for smelting copper ore dating to the second half of the 6th century BC have been discovered in the ancient Greek city of Apollonia Pontica near the Black Sea town of Sozopol (Sozopolis) in southeast Bulgaria.

The kilns were found close to an ancient copper mine in an area known as Medni Rid (Copper Ridge) by a team of Bulgarian and German archaeologists led by Petar Leshtakov and Krasimir Nikov. Dimitar Nedev, Director of the Sozopol Museum of Archaeology:

"The [kilns] demonstrate the highly developed and specialized organization of copper ore extraction and processing within the very mine. This discovery is of extreme significance for Bulgarian archaeology, and perhaps one of the major archaeological events of 2018"

The digs started as rescue excavations in October 2018 after tree logging trucks compromised the terrain, Nedev reveals.The discovery marks the first time ancient metallurgy furnaces have been found near Bulgaria’s Sozopol but outside the immediate territory of the ancient polis.

Amphorae and other pottery imported from the Greek islands of Chios and Samos recovered at the site indicate that copper ore extraction and processing began shortly after the founding of Apollonia Pontica in the early seventh century BC.

The furnaces were found on the northern slope of  'Copper Ridge', and are two types: the first was used for 'frying', that is, removing the sulfur from the copper ore concentrate; the second type were the melting kilns.

The copper ore in 'Copper Ridge' was extracted in an open-air mine, without shafts or tunnels, with a diametre of about 1.2 kilometres. The researchers believe they have also identified three more groups of kilns in the area, and are hopeful of locating the miners’ camp.