Archaeologists have discovered a precious golden dagger dated to about 3,000BC in a Thracian tomb in the centre of Bulgaria.
The alloy used suggests sophisticated metal-working skills
It is the latest find from one of many tombs believed to have formed the cradle of Thracian civilisation.
The dagger, made of an alloy of gold and platinum, was found near the village of Dubovo.
Bozhidar Dimitrov, head of Bulgaria's National Museum, told Reuters news agency the discovery was "sensational".
It is the latest in a string of finds in the area in recent years which has excited archaeologists and has provided more details of the skills of the still mysterious Thracian civilisation.
According to officials at the museum, the dagger is 16cm (6in) long and is sharp enough to shave with.
More than 500 other miniature gold items were found in the same tomb.
The detail on the dagger suggests that it was used for sacrificial purposes.
The Thracian civilisation thrived on the edge of the ancient Greek and Roman empires in what is now Bulgaria, Romania, northern Greece and Turkey, and is believed to have lasted up to 4,000 years.
The historian Herodotus described the Thracian as savage, bloodthirsty warriors and provided a description of the elaborate funeral procedures for their rulers.
Other finds in recent years include a gold mask, an ancient Thracian temple, a crown and thousands of items of jewellery.
The alloy used in the latest find suggests a far greater degree of sophistication in metal-working that was previously known for that period.
"This significant find confirmed that people in this region were familiar with what was then high technology in metal processing," Mr Dimitrov told Reuters.