JACKSONVILLE, FLA. ? Historical records indicate the side-wheel steamer SS Republic was carrying 20,000 gold coins — worth $120 million to $180 million today — in 1865 when a hurricane sent it to the bottom of the Atlantic.

But there could be more. A lot more.

Based on early examination of the sunken wreck by the crew of the ship Odyssey Explorer, coin expert Donald Kagin thinks there could be close to 30,000 gold pieces down there, 1,700 feet beneath the surface.

Either way it will almost certainly be one of the richest shipwrecks ever salvaged. And because it is so far out in international water, salvage company Odyssey Marine Exploration doesn’t have to share the wealth with coastal state governments. The company also gained legal possession of the site in federal court under a principle known as “admiralty arrest” to bar anyone else from laying claim to the treasure.

High-resolution photos taken by a remotely controlled underwater vehicle show a massive pile of coins that looks like something out “Pirates of the Caribbean.”

“This is what we all dream about,” said Kagin, an author and authority on U.S. coins who has been hired to catalog and preserve the treasure.

It’s too early to say how much it will end up being worth, he said.

“This is like predicting the presidential election at 9 o’clock in the morning,” said John Morris, president of Odyssey Marine Exploration, a publicly traded company based in Tampa. “We have a lot of indicators here that make it look really good, but there’s a lot of work to do.”

The discovery in July of the Republic wreck, about 100 miles southeast of Savannah, was the culmination of more than decade of searching by Morris and his partner, Greg Stemm.

This is a photo of the painting Tennessee

Along with their 250-foot Odyssey Explorer, the heart of the project is Zeus, a “remotely operated vehicle” — or ROV — that acts as the crews’ eyes and hands.

The ROV is equipped with cameras and has robotic arms that can handle the most delicate finds. A vacuum system lifts coins and other artifacts into a container to be hoisted to the surface.

“It’s as good as being down there,” said project archaeologist Neil C. Dobson. “In fact, it’s even better because you can get so close. It’s the nearest you can get to getting the archaeologist on site.”

So far, the Odyssey Explorer crew has recovered about 1,750 coins and 300 other artifacts, including the ship’s bell. It could take another three months or so to finish. A National Geographic film team is chronicling the expedition.

The Republic, a 210-foot steamer that was once part of the Union fleet, was carrying 59 passengers and taking money and supplies from New York to New Orleans for post-Civil War reconstruction when it went down.

This Coronet Head 0 Double Eagle coin was plucked off the shipwreck of the S.S. Republic during salvage operations earlier this month.

All the passengers escaped aboard life boats, according to newspaper accounts at the time, but the ship was lost until the Odyssey explorers detected it last summer.