Microdiamond extraction from core samples derived from the Cargo1 and Freightrain kimberlites on Twin Mining (TWG-T) Jackson Inlet diamond property in Nunavut, suggest that diamond grades are continuous to 150 metres and 206 metres, respectively.
Fifteen Freightrain drill samples totalling 1,104.57 kg returned 53 macrodiamonds (stones greater than 0.5 mm in at least one dimension) plus 485 micros. Eight of the macros measure more than 1 mm in two dimensions. The largest stone runs about 2.1 by 1.4 by 0.94 mm.
Twin says the results jive with a previously modeled grade of 0.4 carat per tonne, which was based on mini-bulk sampling in the fall of 2001. The central and northern parts of the pipe surface are reported to be the highest-grade areas.
At Cargo 1, Twin collected 924.7 kg of kimberlite from two holes. The samples surrendered a total of 43 macros and 180 micros. The largest diamond measures about 2 by 1.5 by 1.1 mm.
The two holes are believed to have cut the southwest and northeast edge of the kimberlite body. Both crossed two distinct facies; a coarse olivine macrocrystic autolithic rim, and a dark weakly ashy core zone that appears to be distinctly crater facies.
Twin notes that the results indicate that both kimberlite bodies are low in microdiamond content, which limits the ability to use microdiamond data from small samples to reliably predict macro-diamond grades.
AMEC E&C Services conducted the microdiamond analysis. The company recommends taking a 20-tonne sample from Cargo1 for a preliminary estimate of the macrodiamond grade, and more detailed follow-up sampling on Freightrain.
Twin has a field crew onsite to explore 12 previously identified anomalies. Planned work includes ground magnetometer and gravity surveying, soil sampling followed by drilling.
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