Sure, manganese oxide isn’t exactly gold bullion, but it certainly glistens with a strange, otherworldly sheen. Treasure also makes more sense than scattered plastic bricks, an unlikely inventory item on The Pelinaion, the Greek cargo steamer I’m now exploring. From the moment I descend, it’s clear shipwrecks here are different. I won’t be tracking down any famous, well-preserved vessels — those that, despite their sunken states and lopsided leanings, still seem ready to power up and resume their routes at any moment. In Bermuda, shipwrecks have had it rough.