Papua New Guinea (PNG) has long been known for its rich mineral resources, especially gold.
With vast, rugged terrain and complex geology, it’s a country that continues to catch the eye of the global mining community. And now, a new chapter is unfolding on Tatau Island.
When Australian-based mining company St Barbara discovered high-grade gold anomalies on Tatau, located just south-west of its Simberi operations, it sparked fresh excitement for exploration in one of PNG’s emerging gold regions.
St Barbara rolled out its first large-scale exploration program on Tatau Island between September 2024 and April 2025. The initiative combined hand auger soil sampling, rock chip sampling, trenching, and early-stage reverse circulation (RC) drilling.
And the results? Promising.
The team uncovered widespread gold-in-soil anomalies across 7.3km2, comparable in size to the known anomalies on nearby eastern Simberi Island, home to St Barbara’s producing Simberi gold mine.
Rock chip samples from the Mt Siro – Seraror area revealed particularly promising numbers, including gold assays as high as 22.5 parts per million (ppm). Other strong results came from Mt Tiro, where assays topped out at 2.39ppm.
“This first substantial regional exploration campaign at Tatau Island, the neighbouring island to Simberi, has rewarded us with multiple highly anomalous rock chip and soil samples,” St Barbara chief executive officer (CEO) Andrew Strelein said.
“It extends the anomalous areas around Mt Tiro and at Mt Siro – Seraror, in particular.”
While the numbers are encouraging, the company said this is just the start.
What’s behind the gold?
The gold discoveries on Tatau Island are thought to be linked to a large hydrothermal system, a common source of mineral deposits worldwide and especially in PNG.
Hydrothermal systems form when hot, mineral-rich fluids travel through underground rock, dissolving metals like gold and copper. As these fluids cool, the metals get deposited, sometimes creating significant ore bodies.
In geological terms, the process could be described as nature’s version of brewing a rich, golden coffee – if the coffee pot was buried deep underground for thousands of years.
The broad anomalies in soil and rock found by St Barbara suggest something significant may be forming below the surface. It’s the kind of pattern geologists get excited about, and one that often leads to deeper exploration.
St Barbara is now planning more trenching and RC drilling in key areas on the island. Results from early channel sampling and drilling are expected in the first quarter of the 2025–26 financial year.
Tatau Island isn’t the only place where St Barbara is deepening its involvement in PNG’s mining scene. The company recently announced its plan to acquire a 14.4 per cent stake in Geopacific Resources via a share transaction with Patronus Resources.
That is especially significant because Geopacific owns the Woodlark gold project, another major gold prospect in PNG.
“St Barbara’s existing operational presence in Papua New Guinea through its Simberi gold mine provides deep local experience and strategic alignment with Geopacific’s 100-per-cent-owned Woodlark gold project,” Geopacific said.
Looking ahead
As St Barbara ramps up activity on Tatau Island and explores new collaborations in PNG, the outlook for the country’s mining sector remains optimistic.
“Exploration remains fundamental to sustaining our business,” Strelein said. “Discoveries like those on Tatau Island provide the foundation for future growth and long-term value creation.”
And for PNG, these discoveries offer more than just economic potential. They represent a chance to build stronger partnerships, advance infrastructure, and bring more people into the benefits of the country’s natural wealth.
The Pacific nation is no stranger to large-scale mining. Projects like Ok Tedi, Porgera, and Lihir have shaped the country’s economic development for decades.
PNG’s geology is complex and promising, particularly when it comes to gold and copper.
But like many resource-rich nations, PNG faces a balancing act. Infrastructure limitations, regulatory frameworks, and the need for sustainable, inclusive development all play a role in shaping its mining future.
For companies like St Barbara, it means working not just with rocks and assays, but with governments, local communities, and a broad range of stakeholders to ensure that mining can deliver long-term value for everyone involved.
This feature appeared in the August–September 2025 issue of PNG Mining.
