AKIPRESS.COM - Miners in the tiny Brazilian town of Pindobacu were shocked to unearth the most expensive rock they’ve ever seen: an enormous 360kg emerald worth hundreds of millions of dollars, reports say. 

Digging at the Carnaiba Mine on the North-Eastern shores of Brazil had to be halted when workers stumbled across a rich vein of black rock that glinted green under torchlight.

Slowly and carefully, they dug around the emerald so as not to pierce or shave the precious stone – a mistake that easily could've cost them millions of dollars.

When it was finally freed from the seam, the emerald weighed in at an impressive 360 kg. Being conservative, that would place the worth of the stone in the ballpark of $400 - $450 million.

The emerald, according to local authorities, was sold to a neighbouring mine owner who denied media access and requested anonymity.

It’s quite valid for the buyer to be shy too – in 2001 a similar-sized rock was stolen and taken to the US, where it became the subject of a bitter legal dispute over who's jurisdiction it fell under.

The buyer's lawyer, Marcio Jandir, told G1 Globo that the new owner has no plans to hide the stone away.

"We have already done all the issuance of the certificate of origin, a requirement of DNPM [National Department of Mineral Production]," said Jandir.

"The document has already been issued, and today the owner of the stone is authorized to transit with it in national territory and obviously he wants to do exhibitions with the stone and present in museums and libraries."

If the stone were to be cut and polished, it's estimated it could contain over 200,000 carats of emeralds.