The new golden artefacts are dated back to the end of the fourth or the beginning of the third century BC and were found in the biggest of 150 ancient tombs of a Thracian tribe, the Getae, that was in contact with the Hellenistic world.

The findings also included a golden ring, 44 applications of female figures as well as 100 golden buttons.

"These are amazing findings from the apogee of the rule of the Getae," said Diana Gergova, head of the archaeologist team at the site of the ancient Getic burial complex situated near the village of Sveshtari, some 400 km northeast from Sofia.

"From what we see up to now, the tomb may be linked with the first known Getic ruler Cothelas," said Gergova, a renowned researcher of Thracian culture with the Sofia-based National Archaeology Institute.

One of the tombs there, known as the Tomb of Sveshtari, is included in the World Heritage List of U.N. education and culture agency, UNESCO, for its unique architectural decor with half-human, half-plant female figures and painted murals.

The Thracians, ruled by a powerful warrior aristocracy rich in gold treasures, inhabited an area extending over modern Romania and Bulgaria, northern Greece and the European part of Turkey from as early as 4,000 BC.

They lived on the fringes of the Greek and Roman civilisations, often intermingling and clashing with the more advanced cultures until they were absorbed into the Roman Empire around 45 AD.

Archaeologists have discovered a large number of artefacts in Bulgaria's Thracian tombs in recent decades, providing most of what is known of their culture, as they had no written language and left no enduring records. (Reporting by Tsvetelia Tsolova, editing by Paul Casciato)

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