Bold caption. [Nikolay Doychinov/AFP]

'Indescribable' rush

Some people have turned panning into a full-time occupation as they try to make a living in the European Union's poorest member state.

"It's been two years since we got passionate about it and we haven't stopped doing it, all year round," said Nikolay Kostadinov, 31, who graduated from a mining school and is now "a full-time panner".

His 28-year-old partner Hristo Mavrudov gave up his tourism studies at university to devote more time to his hobby.

"The gold fever is indescribable: you feel a rush of adrenaline when you see something glittering at the bottom of the pan," he says.

The pair said they had collected around 70 grams of gold after combing a number of mountainous rivers across Bulgaria over the past year.

River gold usually has a lower purity of 20 to 22 karats, with jewellers and banks paying 50-52 leva ($29-30) per gram.

"Panners are largely enthusiasts. Those who start doing it with a view to get rich quit very soon. There are no rich panners," Stamenov says.