The only pearl discovered in Indigenous archaeology was apparently spat into a rubbish pile; the shells, on the other hand, were highly prized and traded across the country.

Pearl shell continues to play an important role in Aboriginal culture in the north-west of Australia, and the history of Indigenous trade may reveal an overlooked continental economy prior to European colonisation.

These are some of the stories uncovered by Curious Kimberley's investigation of traditional Indigenous pearling.

Kerry Holland's mother had visited Broome in the 1950s and recounted how strongly the European-Australian pearling industry had shaped the town.

"In the light of our increasing insights into Indigenous culture, it made me think back to that time and wonder," Ms Holland said.

"What did the Indigenous people know about the pearls already, and how were they incorporated into their own story and life?"

This pearl from the Kimberley is 2,000 years old. ( ABC News: Natalie Jones )

Prized catch

The large Pinctada maxima shell was not just more highly valued than pearls, it was one of the most commonly traded items in pre-European Australia, according to WA Museum archaeologist and assistant curator Annie Carson.

"People who have researched pearl shell, and tracking where Kimberley pearl shell has ended up, have argued that they were the most widely traded class of cultural objects in Australia," she said.

Despite not preserving well in many archaeological sites, pearl shell from the Kimberley region has been found in western Queensland, South Australia, central Australia and southern parts of WA.

But there is only one archaeological record of the pearl itself.

"We only know in Australia of one dated pearl," Ms Carson said.

"A tiny, tiny Pinctada albina pearl — it's only about five millimetres in diameter."

It was found in a layer of discarded shells in a north Kimberley coastal rock shelter dated to be 2,000 years old.

"This bed of refuse is most likely from collecting the shell for meat," Ms Carson said.

"This little, tiny pearl was probably spat out by someone chewing away on their meat."

Continuous culture

The Indigenous cultural value of pearl shell is not restricted to the archaeological record.

It continues to be an important cultural and religious artefact in Terry Hunter's everyday life.

Mr Hunter is a Bardi man who grew up on the Dampier Peninsula north of Broome and where he works for the Cygnet Bay pearl farm as a tour guide.

He learnt as a child about the cultural practice of carving pearl shell, known as riji, for ceremony and trade.

"When I was a young fella growing up, I was very lucky to see my father shape the riji the traditional way.

"Also going to initiation ceremonies and seeing all the men dressed in all their mother-of-pearl shells.

"I knew one day I was going to be dressed in a riji as well, so that was something I was looking forward to when I was growing up."

Terry Hunter with two shaped pearl shells, known as riji. ( ABC Kimberley: Ben Collins )

Now as an initiated Bardi man, Mr Hunter travels to communities along the Pilbara and Kimberley coasts, where he has family connections, to take part in initiation ceremonies of young men.

"Each family group throughout the Kimberley and Pilbara coast has their own individual story," he said.

"I can identify what part of the coastline that riji came from just by the designs."

Mr Hunter keeps the riji given to him by his grandfather at his initiation in a safe place, only bringing it out for ceremonies.

Although it was made by his grandfather, Mr Hunter said the design had been handed down the generations for thousands of years.

His ancestors have lived in north-west Australia long enough to have tracked the rise and fall of the sea level with the last ice age.

"A lot of my people saw the ocean move in, especially along the Pilbara coast for my mother's people.

"They were inland people and the saltwater came in, and they became saltwater people."

As well as using pearl shell for riji, Mr Hunter said blank shells were traded with inland groups which used them for their own ceremonial purposes.

"It was a tool for making rain, is my knowledge of the mother-of-pearl shell for the people in the desert," he said.

"We would take the large mother-of-pearl shell inland and trade it for raw material like red ochre, spearheads, spears, boomerangs."

Mr Hunter said he agreed with what the archaeological record suggested was the traditional lack of value of pearls themselves.

"If the old people were to find a natural pearl, it's got no significance to us.

"They'd probably hand it on to the kids, kids would play with it for a while, and it would just get lost in the sand."

Indigenous economy

Writer Bruce Pascoe is a Kulin man from the south coast of New South Wales whose book Dark Emu challenged the perception that Aboriginal people did not farm the land.

Mr Pascoe said there was a similarly incorrect perception that Aboriginal people lived in isolated groups that only engaged through sporadic conflict.

Bruce Pascoe says Indigenous trade helped shape culture, including songlines. ( Matthew Newton, courtesy of Magabala Books )

He said trade, not just of pearl shell, was evidence of another aspect of Indigenous culture overlooked by colonisers and historians.

"In Victoria we have a green stone which was a terrific material to make axes," Mr Pascoe said.

"Those axes have been found around Alice Springs, so they've obviously been transferred from hand to hand along that songline."

Mr Pascoe said songlines could be traced across every part of Australia where language, stories and traded items were passed between Aboriginal groups.

"The North Stradbroke story of the whale and the dolphin and the shark is very, very similar to the story we hear at Broome," Mr Pascoe said.

"It's obvious there's been some transmission across the country of that cultural information."

Mr Pascoe's current research focuses on how Aboriginal people cooperated across the continent — a practice that he believes holds some valuable lessons for the modern world.

"Aboriginal people had a physical economy, a well-managed economy, good government, a pan-national government.

"I'm not saying that Aboriginal people are the wizards of the world, but I'm saying we had a system that lasted 100,000 years — it's worth looking at."