Blackbird
In January 2008, Noront began drilling numerous airborne targets identified on their claims near the Eagle's Nest discovery. In February 2008, drilling at the AT-2 Anomaly, approximately 2 kilometres southwest of Eagle's Nest, intersected low grade magmatic massive sulphide mineralization at Eagle Two. That same drill program also intersected Chromite at Noront's Blackbird deposit.
In February 2009, the company committed $20 to $25 million to completing a drill program designed to allow an initial estimate of chromite resources sufficient to support a 25 year mine life. A total of 154 holes for 52,375 metres were completed at Blackbird.
In December 2009, Noront became the first company in the Ring of Fire to release a 43-101 resource estimate for chromite. The estimate, prepared by R. Gowans PEng., J. Spooner MSc., PGeo., A.J. San Martin MAusIMM and C. Murahwi, MSc., PGeo, MAusIMM, of Micon International Ltd, estimated the initial resources of Blackbird to be:
- Measured resource 5.2 M tonnes @ 34.4% chromite with a Cr:Fe ratio of 1.88
- Indicated resource 6.7 M tonnes @ 35.3% chromite with a Cr:Fe ratio of 1.91
- Inferred resources 6.1 M tonnes @ 33.4% chromite with a Cr:Fe ratio of 1.87
In June 2011, Noront announced that Baosteel Resources had completed a strategic investment in Noront acquiring a 9.9% interest for an investment of $17.4 million. Baosteel's investment funded the completion of the Feasibility Study for the Eagle's Nest nickel sulphide deposit and a drill program to increase the mineral resource at Blackbird.
In March 2012, A.J. San Martin MAusIMM and C. Murahwi, MSc., PGeo, MAusIMM, of Micon International Ltd, updated the Blackbird resource estimate to:
- Measured resource 9.3 M tonnes @ 37.4% chromite with a Cr:Fe ratio of 2.00
- Indicated resource 11.2 M tonnes @ 34.4% chromite with a Cr:Fe ratio of 1.95
- Inferred resources 23.5 M tonnes @ 33.1% chromite with a Cr:Fe ratio of 1.97
The updated resource estimate was based on results from 119 drill holes. Chromite grades were capped at 45% Cr2O3. A cut-off grade of 30% Cr2O3 (with allowance of internal waste to respect geological continuity) was selected to allow for reasonable prospects of economic extraction by comparison with current world producers (e.g. in Finland, Turkey, South Africa, etc). An Inverse Distance Cubed ("ID3") interpolation method was used to estimate model grades. ID3 provides a fairly high level of selectivity, which ensured zones with internal waste remained distinct. The resource model was validated visually by sectioning, and by domain statistical validation and swath plots.
The chromite mineralization at Blackbird remains open at depth and offers an excellent opportunity for further resource increases.