Located in mountainous eastern Russia, this gold mine operates in sub-zero temperatures for most of the year. The large open-pit operation is one of the country’s top producing gold mines.

• Gold mineralisation occurs in complex ore bodies of sulphide sandstones and syenite porphyry
• Blasts are fired in 5 – 6 metre benches and mined in a single pass
• The site contains low grade ore deposits in multiple pits

Challenges

Dilution and ore loss in low grade deposits

• Highly variable blast movement was causing significant dilution and ore loss
• Variation in powder factors created additional variation in blast movement
• Low grade ores required a high level of control to ensure head grade to the processing plant was not diluted

Results

Reduced dilution and ore loss
Recovered US$33,600 in gold

Blast movement
Significant movement occurs within all blasts. Variation of ±50% from the mean horizontal movement is common, and occurs at this operation. In this blast:

• Measured horizontal movement ranged from 1.3 to 4 m (4.5 to 13 ft)

Ore loss and dilution
As a result of accurately accounting for movement in this example blast, the mine:

• Prevented 7% dilution—1,750¹ tonnes of waste was diverted from the mill
• Maximized ore yield—an additional 2,200 tonnes (9%) of ore was sent to the mill
• Recovered 28 ounces of gold, valued at US$33,600², that would have been lost

1. Numbers are rounded
2. Calculated at a gold price of US$1,200/oz.