Rio trenches bulk sample for Star at Star-Orion South


For the first time a trench cutter sampling system is being used to take a bulk sample of a Canadian kimberlite. Such equipment is normally used in specialist foundation engineering, rather than mineral exploration.

The rig cut a hole to a depth of 228.4 metres at the Star-Orion diamond project which is wholly owned by Saskatoon-based Star Diamond. The hole produced 704 bags of kimberlite. The operator of the project is Rio Tinto Exploration Canada.

The trenching rig consists of a Bauer BC 50 cutter mounted on a Bauer MC 128 duty cyclone crane. There is also a kimberlite separation unit and a desanding unit. The kimberlite will be stored in a secure area at the site until a bulk sample plant can be build and commissioned at the project. Rio will undertake final diamond recovery.

Star’s senior VP of exploration and development George Read said, “The successful use of this new trench cutter sampling rig technology for the recovery of kimberlite bulk samples has the ability to revolutionize future bulk sampling and mining of kimberlites, particularly for kimberlites characteristic of the Fort à la Corne diamond district.”