THE world’s most valuable treasure troves are gradually being uncovered, haul by haul, from loots of lost gold worth £15 billion to priceless royal gems.

Over the years as technology has improved, an increasing number of discoveries have been made on the ocean’s floor, from silver coins from the Viking era, to lost royal gems.

Brothers Pavel, Petko and Michail Keikov initially thought the Panagyurishte treasure was a strange whistle when they unearthed it in 1949Credit: AP:Associated Press

A portion of the world’s largest treasure troves are located in shipwrecksSAN JOSÉ

The latest treasure trove to be unearthed was a shipwreck with more than $22 billion worth of gold, discovered at the bottom of the Caribbean.

The huge discovery was made in 2015, though details of the find were kept under wraps until 2018.

According to reports from Nine News, the ship marked the most valuable deep-sea treasure haul to date, and was therefore dubbed the “holy grail” of shipwrecks.

The San José was travelling from Panama to Colombia when it went down on June 8, 1708, during a battle with British ships in the War of the Spanish Succession.

As the British didn’t manage to take the treasure before it sank, it was lost into the void for more than 300 years until it was located by an unmanned underwater vehicle called REMUS 6000.

A shipwreck with more than $22 billion worth of gold, discovered at the bottom of the Caribbean in 2015 (file image)BLACK SWAN PROJECT

The Black Swan project was a 2007 salvage operation that saw the discovery of more than $500 million, or £3.6 million worth of bullion.

At the time, it was the most valuable treasure trove that had ever been found.

The Spanish Government claimed the treasure came from a Spanish vessel – the Nuestra Señora de las Mercedes – which was sunk by British Navy ships in 1804.

However, the identity and location of the ship was oddly never disclosed.

The Black Swan project was a 2007 salvage operation that saw the discovery of more than £3.6 million worth of bullionCredit: HandoutTHE STAFFORDSHIRE HOARD

Terry Herbert was using his metal detector on a recently plowed field near Hammerwich, in Staffordshire, back in 2009 when he stumbled across the largest trove of Anglo-Saxon treasure ever found.

According to Mental Floss, the hoard included several religious artefacts and lots of decorative items.

Believed to be worth around $4.1 million, or close to £3 million, the haul is believed to have influenced the way historians think about that period in English history.

Terry Herbert was using his metal detector on a recently plowed field near Hammerwich in Staffordshire, when he came across the ‘Staffordshire Hoard’Credit: Reuters THE PANAGYURISHTE TREASURE

The Panagyurishte treasure was unearthed by brothers Pavel, Petko and Michail Keikov, when they were digging for clay at a tile factory in Bulgaria.

Their find dates way back to 1949.

What they initially thought was a strange whistle, they later discovered was a ceremonial drinking horn, made from golf.

The piece, which dated back to the 4th century BCE, was thought to be priceless.

TITANIC

The Titantic was carrying more than 1500 passengers and crew members when it went down in the North Atlantic Ocean in 1912, after colliding with an iceberg.

It was also holding a hoard of expensive artefacts, including gold, diamonds, silver and more, though the exact value of the haul isn’t known.

Most of these weren’t discovered until 1985.

As technology improves, an increasing number of discoveries have been made on the ocean’s floorCredit: APLINCOLNSHIRE TREASURE

In another find that’s close to home, a hoard of early fourth centure roman coins was discovered by two metal-detecting enthusiasts in 2017, in Lincolnshire.

Lincolnshire County Council archaeologist Dr Adam Daubney told Sky News that the coins may have been buried as part of a ceremonial ritual.

“The coins were found in a ceramic pot, which was buried in the centre of a large oval pit – lined with quarried limestone,” he said.

“What we found during the excavation suggests to me that the hoard was not put in the ground in secret, but rather was perhaps a ceremonial or votive offering,” he said.

A hoard of early fourth century Roman coins was discovered by two metal-detecting enthusiasts in Lincolnshire in 2017Credit: Reuters