Macraes Mine


Useful Information

Location: At Macraes, 80 km north of Dunedin.
Open: Most days at 10, 14. Booking essential. [2006]
Fee: Adults NZD 20, Children NZD 10. [2006]
Classification: MineGold Mine
Light: LightIncandescent
Dimension:
Guided tours: D=2 h.
Photography:
Accessibility:
Bibliography:
Address: OceanaGold Tours, Toll Free: 0800-465-386. E-mail: contact
Oceanagold Ltd Information Centre, Macraes Rd, Macraes, Tel: +64-3-465-2089, Tel: +64-21-396-270.
Stanley's Hotel, Tel: +64-3-465-2400.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.

History

1850 Macraes area settled by farmers.
1860's discovery of gold.
1875 alluvial mining by individual prospectors ended.
1889 underground mining by the Golden Point Mining Company.
1930 mining reduced.
1954 mining ended, mines closed.
1983 exploration for the mine.
1989 construction activities.
NOV-1990 first gold.
DEC-2004 mine tours started.

Geology

The Macraes mining district lies in the Otago Schist belt. Otago gold deposits are centred on well-defined quartz veins, which were mined historically.

But the new Macraes mine is geologically different, mining a broad shallow-dipping mineralized zone along the Hyde-Macraes Shear Zone. It is up to 150 m thick and slopes 10 to 20° to the northeast. Hot hydrothermal water in the latter stages of metamorphism, about 130-140 million years ago, deposited gold in this shear zone.

The gold content of the mineralized zones averages about 1.5 g/t. This is very low compared to other mines, and it is only economic with large-scale mining.

Description

Macraes mine near Dunedin is operated by New Zealand goldmining company OceanaGold. They opened it for tourist visits to the historic and modern mining operations. During the first 18 months 3,500 people visited the gold mine.

The Macraes mining district was first mined for alluvial gold by individual prospectors. This time ended after only 15 years. The underground mining started and was very successful for forty years. During this time, 15,000 ounces of gold were recovered from the four mines in the area. The mining almost ended in 1930, only small-scale mining remained, and the mines were finally closed in 1954.

The gold field was not empty, but at that time the necessary work was too expensive for the outcome. Today mining technology has developed, mining is now lucrative where it wasn't then. After several years of exploration and one year of construction activities, the first gold was mined in November 1990. Today there are half a dozen mines, both underground and open cast, producing between 162,000 and 185,000 ounces of gold per year. The Macraes mine is the largest active gold mine in New Zealand. Initially it was expected to bear gold for 10 years of operation, but at the moment the remaining gold is estimated to last 35 years.

Mining, especially modern mining, is using chemicals to extract the valuable substances. There is always the problem of pollution, especially in a country like New zealand there is always a lot of work to do to make people comfortable with the idea of large scale mining. It seems the public tours of the mines are a try to increase transparency of the mining operation in an attemt to gain more esteem.