Macraes Mine facts for kids
The Macraes Mine is a very important gold mine in New Zealand. You can find it in East Otago, a region on the South Island. It's the biggest gold mine in the country!
This mine actually has two main parts. One is a huge open-air pit, which started operating in 1990. Imagine a giant hole in the ground where they dig for gold. The other part is a newer underground mine, which opened in 2008. This means miners go deep below the surface to find gold. The mine is located near a small town called Macraes Flat and is owned by a company named OceanaGold.
How Much Gold Does Macraes Mine Produce?
The Macraes Mine is known for producing a lot of gold. Between 2008 and 2010, it produced about 193,000 Troy ounces of gold each year. A troy ounce is a special unit used for precious metals.
Over the years, the amount of gold found in the rock (called "ore grades") has changed. In 2010, for example, there was about 1.26 grams of gold in every tonne of rock. However, the mine has gotten better at getting the gold out of the rock. In 2010, they were able to get out 81% of the gold.
From 1990 all the way to 2014, the mine produced a total of about 4 million ounces of gold. That's a huge amount! In July 2019, they celebrated pouring their 5 millionth ounce of gold. The company believes there's still a lot of gold left to find, and they expect the mine to keep working at least until 2021.
How the Gold Formed
The gold found at Macraes Mine is in special rocks. These rocks were created by powerful natural processes that happened deep inside the Earth. These processes are called orogenic processes. They are responsible for forming mountain ranges and large rock belts.
The gold-bearing rocks at Macraes are part of what is known as the Otago Schist belt. This is a large area of unique rocks in New Zealand that were formed over millions of years by intense heat and pressure.
