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 A team of divers recovered nearly 40 ingots off the sea floor near Siciliy, from a ship that was lost in the sixth century. 
 
 Gleaming cast metal called orichalcum, which was said by Ancient Greeks to be found in Atlantis, has been recovered from a ship that sunk 2,600 years ago off the coast of Sicily. 
 
 The lumps of metal were arriving to Gela in southern Sicily, possibly coming from Greece or Asia Minor. The ship that was carrying them was likely caught in a storm and sunk just when it was about to enter the port. 
 
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 "The wreck dates to the first half of the sixth century," Sebastiano Tusa, Sicily's superintendent of the Sea Office, told Discovery News. "It was found about 1,000 feet from Gela's coast at a depth of 10 feet." 
 
 He noted that the 39 ingots found on the sandy sea floor represent a unique finding. 
 
 "Nothing similar has ever been found," Tusa said. "We knew orichalcum from ancient texts and a few ornamental objects." 
 
 Indeed orichalcum has long been considered a mysterious metal, its composition and origin widely debated. 
 
 According to the ancient Greeks, it was invented by Cadmus, a Greek-Phoenician mythological character. The fourth century B.C. Greek philosopher Plato made orichalcum a legendary metal when he mentioned it in the Critias dialogue. 
 
 Describing Atlantis as flashing "with the red light of orichalcum," he wrote that the metal, second only in value to gold, was mined in the mythical island and was used to cover Poseidon's temple interior walls, columns and floors. 
 
 Today most scholars agree orichalcum is a brass-like alloy, which was made in antiquity by cementation. This process was achieved with the reaction of zinc ore, charcoal and copper metal in a crucible. 
 
 Analyzed with X-ray fluorescence by Dario Panetta, of TQ - Tecnologies for Quality, the 39 ingots turned to be an alloy made with 75-80 percent copper, 15-20 percent zinc and small percentages of nickel, lead and iron. 
 
 "The finding confirms that about a century after its foundation in 689 B.C., Gela grew to become a wealthy city with artisan workshops specialized in the production of prized artifacts," Tusa said. 
 
 The 39 ingots recovered from the wreck were indeed destined to these workshops and were used in high quality decorations. 
 
 According to Enrico Mattievich, a retired professor of physics who taught at the Federal University of Rio de Janeiro (UFRJ), the ingots are not properly made from orichalcum. 
 
 "It appears they are lumps of latone metal, an alloy of copper, zinc and lead," he told Discovery News. 
 
 Mattievich, who has led a number of studies in physics applied to mineralogy, paleontology and archaeology, is one of the scholars who disagree on the brass-like nature of orichalcum. 
 
 While other scholars equated the mysterious metal to amber and to other copper based alloys, Mattievich believes orichalcum has its roots in the Peruvian Andes and in the Chavín civilization that developed there from 1200 B.C. to 200 B.C. 
 
 According to the scholar, who claimed in his book "Journey to the Mythological Inferno" that the ancient Greeks had discovered America, a metallic alloy "with fire-Iike reflections" similar to Plato's description was found in a set of metallic jaguars of Chavin style, which turned to be made of 9 percent copper, 76 percent gold and 15 percent silver. 
 
 Whatever the origins and nature of orichalcum, Tusa's team plans to excavate the shipwreck and bring to light the entire cargo. 
 
 "It will provide us with precious information on Sicily's most ancient economic history," Tusa said. ||||| Read full article | 1 | 2 Continue reading page 
 
 Like an underwater Iron Man, a diver will fly around the wreck of an ancient Greek ship later this year, looking to shed light on the Antikythera mechanism 
 
 THE world's most advanced robotic diving suit is getting ready to help search for one of the world's oldest computers. 
 
 Called Exosuit, the suit has a rigid metal humanoid form with Iron Man-like thrusters that enable divers to operate safely down to depths of 300 metres (see photo). 
 
 Though designed for diving in the bowels of New York City's water treatment plants, earlier this month it underwent its first trials in seawater at the Woods Hole Oceanographic Institution (WHOI) in Massachusetts. The tests are readying the suit for a daring attempt to excavate an ancient Roman shipwreck off the Greek island of Antikythera in the Aegean Sea. A century ago, divers pulled the world's oldest computer – the Antikythera mechanism – from the wreck. They are hoping that they will find a second device when they go down in September. 
 
 Marine archaeologists normally wear scuba gear to explore underwater sites in person, but the time that divers can spend at depth is limited by the dangers of decompression sickness, or the bends. For deep wrecks, researchers rely on remotely operated vehicles (ROVs) carrying cameras and sonar to scan an area, or large and expensive craft like the Alvin submarine that explored the wreck of the Titanic in 1986. 
 
 The $1.5 million Exosuit falls somewhere in between. "It's basically a wearable submarine," says Phil Short, a diving specialist on the planned mission to Antikythera. "The pressure inside is no different from being in a submarine or in fresh air. We can go straight to the bottom, spend 5 hours there and come straight back to the surface with no decompression." 
 
 The suit is made from an aluminium alloy, with articulated joints that permit divers to move their arms and legs freely. An umbilical cable from a ship supplies it with power for horizontal and vertical thrusters, and a rebreather that scrubs toxic carbon dioxide from exhaled air, giving 50 hours of life support. The cable also carries voice, video and data links. In the event of an emergency, a battery can power everything but the thrusters, including a back-up communication system. 
 
 Foot pedals inside the Exosuit control the four thrusters to manoeuvre it through the water. And if a diver is busy with a complex task underwater, an operator topside can monitor the Exosuit's video feed and fire the thrusters to keep it in position – or even take over completely and bring the suit back to the ship. 
 
 The Exosuit is needed both because of the depth of the Antikythera wreck – it reaches 120 metres – and the delicacy of any artefacts that might lie within. When Greek sponge fishermen found the shipwreck in October 1900, the pressure was such that they had only 5 minutes on the seabed before having to ascend. It was risky: several divers were paralysed and one died from decompression sickness. 
 
 By the time underwater explorer Jacques Cousteau led an expedition to the ship in 1976, the amount of time that could be spent at the bottom had been extended to just 10 minutes. To maximise their efficiency, Cousteau's divers used a vacuum system to suck up a small area of the wreck, but this risked damaging or destroying priceless fragile objects. 
 
 The new expedition won't face such time constraints. "With the Exosuit, our bottom time becomes virtually unlimited," says Brendan Foley, co-director of field operations at WHOI's Deep Submergence Laboratory. "Now we can have an archaeologist in the suit for hours, and we'll only have to come up to answer the call of nature." 
 
 Despite the limitations of earlier expeditions, the treasures that were recovered at Antikythera represent some of the finest ancient Greek and Roman artefacts in existence. They tell the story of a Roman ship that foundered on the rocky shores of the island around 60 BC. The ship was laden with luxury goods, including bronze and marble statues, precious jewellery, a hoard of coins, glassware, ceramic jars – and fragments of a peculiar geared device whose importance was at first overlooked. Only in the 1950s did scholars figure out that the rusty metal pieces could be assembled into a sophisticated analogue computer for predicting astronomical events. They called it the Antikythera mechanism. 
 
 Ironically, 2000 years spent in corrosive saltwater may have been the best way to preserve these riches. Most precious objects from antiquity have been broken up or melted down over the millennia. The National Archaeological Museum in Athens has only 10 major bronze statues from Ancient Greece – and nine of them came from shipwrecks. 
 
 Foley believes that the Antikythera shipwreck still holds many secrets. A preliminary survey last year showed artefacts scattered over an area 50 metres by 10 metres, and even revealed a previously unknown shipwreck alongside the first one. 
 
 "We have feet, arms and the crest of a warrior's helmet from statues recovered in 1900 – maybe we'll get lucky and find the rest of them," says Foley. "But for me, the mechanism is what sets this wreck apart. It's the questions it opens up about the history of science and technology that fire my imagination." 
 
 Read full article | 1 | 2 Continue reading page 
 
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– It was considered one of the most precious metals in ancient times—and Plato claimed it lined the temple of Poseidon on the legendary island of Atlantis—but this appears to be the first time anybody in modern times has actually found some orichalcum. Researchers in Sicily say a shipwreck from 2,600 years ago, not long before the time of Plato, has yielded 39 ingots of the mysterious metal, Discovery reports. Scholars have long debated the composition of the alloy mentioned in ancient writings, but testing has revealed the Sicily ingots to be a copper-zinc mix with small percentages of nickel, lead, and iron. "Nothing similar has ever been found," says the superintendent of Sicily's Sea Office. "We knew orichalcum from ancient texts and a few ornamental objects." He tells the Giornale di Sicilia that the ingots were apparently bound for workshops in the town of Gela, probably coming from Greece or Asia Minor, when the ship transporting them sank. The find, he says, "opens prospects of great importance to the research and study of ancient routes of supply of metals in the ancient Mediterranean. ... It will provide us with precious information on Sicily's most ancient economic history." (Divers recently found a "holy grail" of shipwrecks.)