Rare jade artifact found on Emirau

WHAT does Emirau Island in New Ireland’s St Mathias Group and Lake Sentani in Indonesia’s West Papua province have in common?
Jade. Yes, jade – that semi-precious green stone that one usually associate with fine jewellry and other intricate works of art and craftsmanship for nobility from ancient Chinese dynasties that today grace the museums of the world, notably the Forbidden Palace in Beijing.
Noted expert on Lapita settlements in the Bismarck Archipelago Prof Glenn Summerhayes of Otago University in New Zealand this week alerted me to the intriguing connection between Emirau and Lake Sentani, about 1,00km over the ocean to the west.
Summerhayes told The National that more will be revealed in an article coming out in a few weeks in the esteemed science periodical “European Journal of Mineralogy”.
“The article is about a jadeite gouge we found from Emirau in 3,300-year-old contexts that originated from near Lake Sentani.
“The paper will have my colleagues from the museum and Emirau in the acknowledgements. I’ll send you the full paper when it comes out in a few weeks,” he said.
Apart from Summerhayes and Otago colleague Lisa Matisoo-Smith, the other co-authors of this article are Prof Hugh Davies from the University of Papua New Guinea and Prof George Harlow from the American Museum of Natural History.
Said Harlow in a media statement this week: “In the Pacific, jadeite jade as ancient as this artifact is only known from Japan and its usage in Korea. It’s never been described in the archaeological record of New Guinea.”
During the past year Summerhayes and the international team of archaeologists and geologists came to the conclusion that what found was an extremely unusual example of jade in the southwest Pacific, thousands of kilometers away from the nearest known geological source.

They concluded that the small green artifact was about 3,300 years old and “had a chemical composition that is unlike any other described jade”.
The rock, found during a series of archaeological excavation on Emirau carried out two years ago by Summerhayes and his team from Otago, was thought to have been used as a wood gouge by the people living there.
But where did it come from?
That is the question that the researchers will be addressing in the upcoming special issue of the European Journal of Mineralogy on jadeitite, the rock that defines one type of jade.
The statement from the American Museum of Natural History said that after investigating the possibility of sources in Asia and coming up empty-handed, Prof Davies of UPNG came across a clue in the form of an unpublished manuscript by German scientist C. E. A. Wichmann.
Wichmann, a professor at Utrecht University in the Netherlands, collected some curious rocks from the Torare River, close to Lake Sentani and Jayapura in the beginning of the 20th century.
According to Wichmann’s manuscript, the rocks he collected had chemical properties that were very similar to the Emirau Island jadeite, the researchers found.
“Harlow is now investigating samples from Wichmann’s collection, on loan from the Institute of Earth Sciences at Utrecht University and the National Museum of Natural History in Leiden, to determine if a new source for this unusual type of jadeite has been found.
“So far, the data support the hypothesis,” the statement said.
“The discovery of this artifact’s source can be eagerly anticipated as something geochemically extraordinary,” Harlow said.
Said Summerhayes; “This jadeite tool points toward prehistoric contacts with the north coast of New Guinea.
“The users of this jadeite gouge were part of the movement of Austronesian-speaking people we call Lapita, who appeared in the western Pacific almost instantaneously around 3,300 years ago, then quickly spread across the Pacific out to Samoa in a couple hundred years, and from there formed the ancestral population of the people we know as Polynesians.
“Where they came from beforehand has always been a matter of debate, so any find linking these early Lapita settlements with the west is important in modeling the nature of their beginning.”
Summerhayes returns to PNG next week to continue more research at Ivane Valley of Goilala district, Central province, where two years ago he and his team from UPNG found evidence of a 50,000-year-old occupation.
Perhaps, then will he give us more insights into the use of jade by our Lapita ancestors as they trekked across the Pacific.