The find "was what I'd been waiting for, for 20 years," Noli said. "Understandably, I was pretty excited. I still am."
Noli brought in Bruno Werz, an expert in the field, to help research the wreck.
Noli has studied maritime artifacts with Werz, who was one of his instructors at the University of Cape Town.
The pair is now trying to piece together the story of the wreck.
They divide their time between inventorying the find in Namibia and doing research in museums and libraries in Cape Town, South Africa, from where Noli spoke by phone Thursday.
Eventually, they will go to Portugal or Spain to search for records of a vessel with similar cargo that went missing.
Noli compared the remnants—ingots, ivory, coins, coffin-sized timber fragments—to evidence at a crime scene.
"The surf would have pounded that wreck to smithereens," he said.
"It's not like 'Pirates of the Caribbean,' with a ship more or less intact."
The wealth on board is intriguing, Noli said. The large amount of copper could mean the ship had been sent by a government looking for material to build cannons.
"You don't turn a skipper loose with a cargo of that value and have no record of it," he said.
Trade in ivory was usually controlled by royal families, another indication the ship was on official business.
On the other hand, why did the captain have so many coins? Shouldn't they have been traded for the ivory and copper?
"Either he did a very, very good deal. Or he was a pirate," Noli said.
"I'm convinced we'll find out what the ship was and who the captain was."
What Caused the Shipwreck?
What brought the vessel down may remain a mystery. But Noli has theories, noting the stretch of coast was notorious for fierce storms and disorienting fogs.
(Read related story: "Grim Life Cursed Real Pirates of Caribbean" [July 11, 2003].)
In later years, sailors with sophisticated navigational tools avoided it.
The only tools found on the wreck were astrolabes, which can be used to determine only how far north or south you have sailed.
"Sending a ship toward Africa in that period, that was venture capital in the extreme," Noli said.
"These chaps were very much on the edge as far as navigation. It was still very difficult for them to know where they were."
Noli has found signs that worms were at work on the ship's timber, and sheets of lead used to patch holes, indications the ship was old when it went down.
Imagine a leaky, overladen ship caught in a storm, he said. The copper ingots, shaped like sections of a sphere, would have sat snug, but the tusks—some 50 have been found—could have shifted, tipping the ship.
"And down you go," Noli said, "weighed down by your treasure."
Associated Press Writer Lily Hindy in New York contributed to this report.