Anomalous kimberlitic garnets were first identified by BHP Billiton during sampling in 2000 and 2001. Work conducted by Dunsmuir last year outlined a well-defined indicator mineral train. The train appears to result from several kimberlite sources. It measures about 35 km long by 6-7 km wide. The company says the pyrope train "is dominated by G-9 garnets with subordinate eclogitic garnet (some with diamond stability compositions), chrome diopside, olivine, and chromite (some with diamond stability compositions). Fragile surface textures on the G-9 garnets suggest a proximal kimberlite source and include a single G-9 grain with kimberlite attached and multiple grains with kelyphitic rims."
A second indicator train about 40 km south of the Nanuq train is also being traced. It contains purple garnets with subordinate orange garnets, olivine, chrome diopside, and chromite. Electron microscopy will be done this spring to confirm the mineral chemistry.
A map of the Nanuq train and more information on the project are available at Dunsmuir Ventures.
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