The Britannia Mine Concentrator was designed to perform one essential task: separate valuable copper minerals from waste rock. At its peak, the Mill processed enormous quantities of ore and became known for the efficiency of its mineral-processing methods.
Before the stock market crash of 1929, the Concentrator was processing as much as 6,500 tons of rock per day, producing chalcopyrite, an important copper-bearing mineral.
From Rock to Fine Ore
After arriving at the Mill, the mined ore passed through several stages of crushing and grinding. Large ball mills reduced the material until it reached a very fine consistency.
Grinding was necessary to separate the valuable mineral particles from the surrounding waste rock and prepare the material for the next stage of processing.
Froth Flotation
One of the most important processes used at Britannia was froth flotation. The finely ground ore was mixed with water and chemicals, allowing valuable minerals to attach to bubbles and rise toward the surface while much of the unwanted material remained behind.
This process significantly increased the concentration of copper in the final product.
Increasing the Copper Concentration
Ore arriving at the Mill contained an average of approximately 1.25% copper, equivalent to about 25 pounds of copper per ton of ore.
After processing, the resulting concentrate could contain around 26% copper, or approximately 520 pounds per ton. This dramatic increase demonstrates how effectively the Mill separated valuable minerals from waste material.
Britannia became particularly well known for its flotation technology, including a technique that became known as the Britannia deep cell method.
Improving the Process
Efficiency was essential to the profitability of Britannia Mine. Engineers continually modified equipment and processing methods in an effort to recover more valuable minerals from every ton of ore.
These improvements helped the Britannia Concentrator develop a reputation as a highly productive mineral-processing facility and made the Mill an important part of Canada’s copper-mining and industrial history.