Mike Poben is an Adelaide-based opal dealer so he is used to dealing with precious stones. But in 2013, he stumbled upon a particularly extraordinary find after purchasing a bag of rough opals from some miners in New South Wales, Australia.
He told National Geographic Australia, there was one unusual piece in the collection that grabbed his attention. It turned out to be the opalized fossil of a fragment of a lower jaw bone. When he checked the bag a second time, he spotted another.
In 2014, paleontologist Phil Bell discovered that the two fragments formed the lower jaw bone of a dinosaur. And it's not just any old dinosaur. It is a never before seen dinosaur species, now described in a study published in the journal PeerJ for the first time.
Meet the brilliantly-named Weewarrasaurus pobeni, a reference to the place where it was found (the Wee Wara opal field, close to Australian outback town Lightning Ridge) and the man who found it (Poben). It is the first dinosaur species to be discovered and named in New South Wales in almost a century.
Despite the fact that the only clue to this dinosaur's existence is a single fossilized jaw bone – albeit a spectacularly jazzy one – paleontologists are able to paint a remarkably detailed picture of this animal's image and lifestyle. We know, for example, that it is a type of dinosaur called an ornithopod, a group that also counts Parasaurolophuses, Iguanodons, and Hadrosaurids among its members.
Ornithopods like W. pobeni are bipedal running grazers. This particular species would have lived during the Cretaceous, been roughly the size of a labrador, and moved in small groups to avoid being attacked. According to Bell, it had a beak and teeth designed for vegetation.
Less is known about dinosaurs that lived in the southern supercontinent of Gondwana than their relatives in North America and Eurasia – though the number of named Australian species is growing.
"If these fossils were in surface rock, like those found in China and Mongolia, it would be an absolute treasure-trove," Bell said in a statement.
"Unfortunately, the fossil remnants we see are almost always part of mining spoil, because they sit in rock strata that lies up to 30 metres underground."
One thing that makes Australia unique is the plethora of smaller ornithopods, where there was less competition from larger dinosaurs.
"Small ornithopods had free range to feed on as much vegetation as they liked and evolved into many different species," Bell told National Geographic Australia.
Back then, this part of New South Wales (now dry and dusty) would have been an area lush with lakes, waterways, and shrubland. The climate would have been temperate, rarely dipping below 4°C (39°F) but due to its location – further south than it is today and as close to the South Pole as the Finnish city Helsinki is to the North Pole – its winters would have been long and dark.
As for the location of this new find, Bell describes it as a “truly unique area”.
"There’s no place in the world like this, where you have dinosaurs preserved in beautiful opal", formed over a period hundreds of thousands of years from a solution of silicon dioxide and water.
He and his team have now begun examining a number of other opalized fossils, which they believe will be described as new species in the future.