The past is full of buried secrets — and sometimes, it opens its mysteries to us. Lately, thanks to high technology and a lot of luck, some priceless treasures that were lost to time have been found again. Check out a gallery of astonishing artifacts that have been returned to us recently.

Top image: The Bactrian Treasure, via National Gallery of Art.

The Sevso Treasure, a hoard of silver objects from the first century, found by a young Hungarian soldier named Jozsef Sümegh in 1975 or 1976. Sümegh and some of the others who knew about the treasure died mysteriously within the next few years.

The first pieces appeared in London in 1980, and were acquired by a consortium led by Spencer Compton, 7th Marquess of Northampton. Some documents from the Lebanese Embassy in Switzerland claimed that the treasure was theirs. In 1990 the treasure was put up for a sale by Sotheby's in New York, described as silver objects from the province of Phoenicia, but the sale was halted when the documentation was found to be false. After that, the governments of Hungary, Lebanon and Yugoslavia all made claims of ownership, but nothing was resolved.

(via Illicit Cultural Property and Index)

The Bactrian Treasure (or Bactrian Gold), a 2000-year-old treasure collection of more than 20,000 gold items from six burial mounds, found in 1978 by a team of Soviet archeologists led by Viktor Sarianidi, shortly before the Soviet invasion of Afghanistan.

The collection went missing for more than two decades, but was found in secret vaults underneath a bank in Kabul.

The pieces include necklaces set with gems, crowns, medallions, figurines, belts and coins. More photos can be seen here.

(via Wikimedia Commons, Artsjournal and National Gallery of Art)

One of only 25 known surviving copies of the Declaration of Independence which were printed in July 4, 1776, found behind a painting bought by a Philadelphian man at a flea market for only $4 in 1989. It was sold for $2.42 million in 1991 and again in 2000 for $8.14 million.

(Photo by Chris Hondros/Newsmakers)

250,000 intact Vietnamese ceramics from the 15th century were found on Hội An wreck, discovered by local fishermen in the early 1990s, 22 miles off the coast of Vietnam in the South China Sea.

The excavation process took four years between 1996 and 2000 and cost more than $14 million. 90 percent of the found ceramics were sold at auctions since then.

(via Dargate and eBay)

The Vale of York Hoard (or the Harrogate Hoard), a 10-century Viking hoard of 617 silver coins and 65 other items, including arm rings, brooch fragments and neck rings, found by David Whelan and his son with a metal detector in 2007 near Harrogate, North Yorkshire, England.

(via British Museum and Wikimedia Commons)

The SS Port Nicholson, a British cargo ship, torpedoed by the German U-87 on 16 June 1942, discovered by Greg Brooks in 2008, 50 miles (80 km) off Cape Cod. The ship was carrying platinum, gold and industrial diamonds (worth more than $4 billion now) as a payment from the Soviet Union for material delivered under Lend-Lease.

According to this PRWEB article, the Sub Sea Research team cannot bring up the cargo yet — but they're working on a stronger and better rover.

(via Wrecksite)

The Staffordshire Hoard, discovered in July 2009 by Terry Herbert on a recently ploughed farmland with a metal detector, near Lichfield, Staffordshire, England.

The first excavation resulted more than 3,500 pieces of 7th-century Anglo-Saxon gold and silver metalwork, but in December 2012 91 additional items were found nearby.

A sword hilt plate

A strip of gold with a biblical inscription in Latin

(via Wikimedia Commons, AP Photo/Kirsty Wigglesworth and Christopher Furlong/Getty Images)

More than 1,400 lost paintings were re-discovered in the home of recluse collector Cornelius Gurlitt in Munich, 2011, including the works of Max Liebermann, Henri de Tolouse-Lautrec, Paul Cézanne, Albrecht Dürer, Edgar Degas, Edvard Munch, Pablo Picasso, Paul Klee and Marc Chagall with an estimated worth of $1.3 billion.

The confiscated and stolen works were collected by Cornelius' father Hildebrand, who was an art dealer and historian.

(via JapanTimes)

The biggest archeological find of the century: Six underground chambers full of treasures were discovered in the 16th-century Sree Padmanabhaswamy Temple in southern India, 2011.

There was a golden bow, a golden rope, golden coconut shells, hundreds of gold coins, emeralds, bangles, one ton of gold in the shape of rice trinkets, 37 pounds of gold coins from the East India Company, 18 Napoleonic coins and a one-foot tall golden statue of Vishnu, decorated with gems. The treasure is worth an estimated $8 billion, and made the temple the richest in India.

(AP Photo/Aijaz Rahi)

The Naryshkin silver, found in the former home of the aristocratic Naryshkin family by construction workers in March 2012.

The family left the building and the city in 1917, and the values had been moved out of the house in 1920, but during the last restoration work, workers came across a tiny secret chamber (10 by 6.5 feet or 3 by 2 metres) filled with 49 sacks of gems containing silver dinner sets and porcelain items, among others.

(via The History Blog)

The largest precious metal discovered in a shipwreck: 110 tons of silver were found 15,400 ft (4,700 meters) down in the Atlantic Ocean, off the coast of Ireland, 2012-2013

The treasure was sunk in 1941 with the SS Gairsoppa, a British steam merchant ship that carried silver, pig iron and tea from India to Great Britain. It was torpedoed by a German U-101.

(Photo by AP/Odyssey Marine Exploration, Inc.)

A gold treasure worth $300,000 found by the treasure-hunting Schmitt family and a diver, Dale Zeak, off the coast of Fort Pierce, Florida in September 2013.

The treasure includes 64 feet (19.5 m) of gold chain, a gold ring and five gold coins been there for almost three centuries.

(via Booty Salvage)