De Beers
Exploration Stages
Early Exploration
Prospective exploration targets are identified by conducting desktop studies. Early exploration usually consists of reconnaissance work in the identified target areas. Soil samples are excavated or stream samples are collected by hand. Where the ground is unsuitable for hand sampling, airborne geophysical surveys are used to identify features that could indicate the presence of kimberlites – the host rock for diamonds. This type of work causes little or no environmental impact.
Follow-up Exploration
This stage examines areas of interest identified during reconnaissance and uses many of the same techniques (sampling, surveys, etc.). At this stage, the work is concentrated in relatively small areas, usually 10% of the original work area.
Geophysics plays an important role in this stage of exploration. Sites of potential interest identified during the airborne magnetic surveys are investigated either on the ground by geophysicists or using a helicopter-borne magnetic or electromagnetic system which flies small pattern surveys over blocks of land. Ground geological mapping is also likely to be used during this stage of work.
Target Delineation and Evaluation
Most diamond projects are particularly sensitive to grade (carats per tonne) and revenue (dollars per carat). Therefore, these are the first parameters to be determined during the evaluation process.
To reach this stage is rare, as kimberlites are hard to find, and many do not contain diamonds. At this stage, any anomalies, or irregularities, which could suggest the presence of kimberlites are examined in one of three ways.
Core Drilling:
To test these anomalies and discover what caused them, a small diameter core hole is drilled. If the material is kimberlitic, the rock sample is analyzed for the presence of microscopic diamonds (diamonds smaller than 0.5mm in at least two dimensions).
Mini Bulk Sampling:
Where such diamonds are found in appreciable quantities, a mini-bulk sample (of several tonnes) is then taken, usually by drilling, to test the kimberlite and obtain a better first estimate of the diamond grade. If the results from the mini-bulk sampling are promising, then a full evaluation programme is undertaken, using bulk samples.
Bulk Sampling:
Bulk sampling usually involves trench or pit excavation as well as large diameter drilling to extract bulk samples. Before the work begins, an environmental baseline study is undertaken. The application of geochemical methods adds value in this process by providing information at an early stage on the diamond-bearing potential of a kimberlite.
If the exploration stages confirm the presence of ore bodies with the potential to become mines, they are further tested. This constrains the size of the ore body, its shape below the surface to a depth of at least 200m (600 feet), and provides additional bulk samples used to determine both the diamond grade (the weight of diamonds per tonne of kimberlite) and value per carat for the diamonds.
Source: https://www.canada.debeersgroup.com/Exploration/Exploration-Stages/
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Heavy Equipment Operator (Multiple Positions)
Reporting to the Mine Supervisor, these positions will be responsible for competently operating heavy mobile equipment including but not limited to haul trucks, dozers, graders, loaders, excavators and/or shovels to safely maximize the mine production of ore and waste in the mine pit.
Mine Hydrogeologist
Installation, commissioning, operation & maintenance of centrifugal and submersible pump fleet.
Site Services Superintendent
The Gahcho Kué Project is an exciting new diamond mine under construction in the Northwest Territo-ries, Canada.