The Dunedin City Council has bought a piece of Otago Peninsula land without, seemingly, being aware of its gold-bearing potential.
In January, it paid $2.6 million for 328ha near Portobello called Harbour Cone, which, it transpires, is partly made up of gold and silver.
Since 1872, at least four shafts have been dug into its steep southeastern side, producing evidence of both gold and silver.
Peninsula interests pushing for the council to buy the land were aware of past mining interest in Harbour Cone, but it was news this week to the Harbour Cone steering group chairman, Cr Dave Cull.
"Nobody has mentioned it to me up till now," he said.
The steering group is awaiting a report from consultant archaeologist Angela Middleton, who is researching the property's history.
She said she had not found signs of gold-mining activity on the property, but believed the "real gold" lay in its rich farming history.
Peninsula community board chairwoman, Irene Scurr, said that when trying to convince councillors to buy Harbour Cone, the property's gold-mining past was "mentioned, but it wasn't highlighted".
Although gold-mining at Harbour Cone has been sporadic over the past 136 years, large-scale open-cast mining was considered a prospect in the early 1980s.
University of Otago geologist Dr Dave Craw recalled the controversy.
"The locals got up in arms because there was going to be exploration there and they didn't like the idea of having a gold mine in their area."
Lala Frazer, of Save the Otago Peninsula, said this week local residents objected because they believed mining would be on the same scale as that at Macraes.
She said there were suggestions Hoopers Inlet was considered a suitable site for the disposal of thousands of tonnes of rock, and that a four-lane service road would be built across the peninsula.
In 1984, geologist Al McOnie produced a report for now defunct Wellington company Circular Quay Holdings Ltd, which noted "low order" gold values in rock from near the old mine and in nearby Battery Creek.
Although Mr McOnie considered the results were "worthy of further investigation", he recommended the company withdraw, as the area represented "a low priority target at the present time".
Mr McOnie had considered a drilling and geophysical survey would be required, "possibly involving some work over water-covered areas".
Dr Craw said some prospecting had been done as recently as two years ago.
Most of Otago's gold is in schist rock, and finding gold in Dunedin's volcanic rock was considered surprising.
"It just stands out as being very unusual in Otago to have gold in the volcanics, but that doesn't mean it can't happen. It does happen," he said.
Suggestions the Harbour Cone mine might have been "salted" with gold have been around almost as long as the first mine.
However, the late Hardwicke Knight, in 1984, examined this theory and concluded that reports of gold at Harbour Cone were genuine, and the reason the mine had been abandoned lay with the type of rock in which the gold was held.
"The hardness of the matrix and the fact it had to be sent to Melbourne for proper crushing were sufficient reasons to account for the mine being abandoned."
