Latin American silver mine created US$260,000 additional value

Latin American silver mine

Commodity Ore Grade Geology Powder Factor Location
Silver High Structured 0.9 kg/m3 Latin America

This operation is one of the top producing open-pit silver mines in the world.

  • Deposits are structurally-controlled in low to medium sulphide veins
  • Drills and blasts 7.5 m benches, mined in a single pass
  • Contains high grade (60 g/t) silver mineralisation with gold as a by-product


Selective mining in a structurally-controlled deposit generated reconciliation issues when ore polygons move outside their original boundaries
  • Ore loss: unaccounted blast movement means material containing high grade silver ore is sent to the waste pile
  • Dilution: tonnes of waste are unintentionally sent to the mill
  • Misclassification of ore: high grade ore is stockpiled as low grade or low grade ore is sent to the mill as high grade


The BMM System accurately measured blast movement and translated post-blast dig lines
  • Blast movement monitors (BMMs) were installed in monitoring holes throughout the shot
  • Installation and detection as per site standard operating procedures
  • BMM Explorer software calculated new dig lines, and areas of ore loss and dilution that would have occurred without monitoring


Significant increase in ore recovery adds $260,000 of value—in one blast

Significant movement occurs within all blasts. Variation of ±50% from the mean horizontal movement is common and occurs at this mine.

  • Measured horizontal movement ranged from 7.3 to 10.5 m (24 to 36 ft) and vertical movement of up to 1.4 m (5 ft)

As a result of accurately accounting for blast movement, this mine:

  • Maximized ore yield—6,100* tonnes of ore were recovered, valued at US$200,000*** (avoided 30% ore loss)
  • Reduced dilution—6,000 tonnes of waste were diverted from the mill, resulting in 30% dilution and $60,000**** of unnecessary milling costs
  • Prevented misclassification—1,200 tonnes (6%) of ore would have been misclassified

* Numbers are rounded
** Average grade of ore polygons
*** Calculated at a silver price of US$19/oz.
**** Calculated from milling costs of US$10 per tonne

Accounting for blast movement improved ore recovery, adding US$260,000 of value—in one blast

latin america silver mine structured