Macraes: New Zealand's Largest Operating Gold Mine

Drive inland from Palmerston on the Otago coast, past rolling tussock hills and sheep stations, and you'll eventually reach one of the most significant mining operations in New Zealand history. The Macraes Mine isn't a relic of the 1860s gold rush — it's very much alive, producing gold today on an industrial scale.

A Different Kind of Gold

Gold was first discovered at Macraes Flat in 1862, around the same time as the major strikes at Gabriel's Gully and the Shotover. But the gold here was different. It wasn't sitting in river gravels waiting to be panned. It was locked deep within a massive schist formation, disseminated through the rock in particles too fine to see with the naked eye.

The 19th-century miners tried — and some did manage to extract gold from the quartz veins — but the technology of the time couldn't efficiently process the low-grade, finely disseminated ore. The area was mined sporadically but never became a major producer.

That changed in the 1980s, when modern exploration techniques identified the true scale of the deposit.

The Modern Mine

OceanaGold began operations at Macraes in 1990. What they found was one of the largest orogenic gold deposits in the world — a massive mineralised zone stretching for kilometres through the schist bedrock.

The operation today includes both open-pit and underground mining. Ore is trucked to a processing plant where it's crushed, ground, and treated using modern extraction methods. The gold content is low by historical standards — typically just a few grams per tonne — but the sheer volume makes up for it.

Since 1990, Macraes has produced over 5 million ounces of gold. That's more than the entire Otago gold rush produced in its first decade. The mine employs hundreds of people and contributes significantly to the regional economy.

What It Means for Prospectors

Here's the thing about industrial gold mining: it operates on a completely different scale than recreational prospecting. Macraes processes millions of tonnes of rock to extract gold that would be invisible to anyone with a pan.

But the geology that makes Macraes viable also explains why Otago's rivers still contain gold. The same schist formations that host the Macraes deposit have been eroding for millions of years, releasing gold particles into the waterways. The alluvial gold in the Arrow River, the Shotover, and Gabriel's Gully all trace back to these ancient geological processes.

In a sense, Macraes represents the source — and the fossicking areas downstream are where nature has done the concentrating for you.

Visiting the Area

The Macraes Mine isn't open to casual visitors, but OceanaGold occasionally runs educational tours. The Macraes township has a heritage centre that tells the story of gold mining in the area, from the 1860s rushes to the modern operation.

For fossicking, the nearby Gabriel's Gully — where the Otago gold rush began — remains open to the public.