The discovery of a second Gweagal shield and an engraved boomerang in the museum’s basement, packed away and ready to be shipped to a new location, left Mr Kelly with mixed emotions.

“It was a really powerful moment,” he said.

“I was so happy to hold them and when it was time to pack them away and I had to leave I got really upset, but happy we’d found them.”

The discovery came while scouring the pages of the museum’s 18th Century Australian catalogue.

Mr Kelly was stunned to see an entry reading “Botany Bay 1770”, the year Captain Cook and his crew landed at Botany Bay after wounding Mr Kelly’s sixth-times great grandfather in the leg with a bullet from a musket.

“They seemed way better than the British, so I'd love to start the repatriation process with them as soon as possible,” Mr Kelly said.

“It is starting to look up for our culture and if we can get them back we can teach the kids how to make them.”

The objects match descriptions from diary entries by both Cook and Joseph Banks, and the boomerang appears ceremonial, Mr Kelly said.

“It has carved designs on it with ochre in the grooves, so I reckon they were ceremonial,” he said.

“Each person would have had two each so there’s got to be more out there somewhere.”

The team of activists traveling with Mr Kelly are now looking into old records from auction houses to check if anything has been sold and the Swedish are searching their museums for Australian items.

“The Germans said they bought the items at auction in the 1800s, but the cards were lost in World War 2, so the information has only just been rediscovered,” he said.

“The Germans have been really good apart from the Grassi Museum in Leipzig who wouldn’t let us in the basement, but the curator is working on a project to help repatriation.

“The trip so far has proven we have no idea what else is out there.”