Resource Modelling

On 26 October 2009 Golden West Resources announced that it had completed another significant resource upgrade at the Wiluna West Hematite Project. For the first time the inventory includes an Indicated Mineral Resource category totalling 42 million tonnes (Mt) at 60% Fe (30% of the total resource). The total Mineral Resource is now 141Mt at 59% Fe with deleterious elements within sales specifications.
This upgrade of GWR's Mineral Resources confirms that the Wiluna West Hematite Project is a major deposit in the Midwest Region. The Mineral Resource inventory places Wiluna West as the second largest hematite deposit in the Midwest Region reconfirming the Board's confidence in the project. These results represent another major step towards the development of an operating mine at the Wiluna West Hematite Project.
Highlights
Significant resource upgrade at the Wiluna West Hematite Project Indicated Mineral Resource Estimate category totalling 42 million tonnes (Mt) at 60% Fe (30% of the total resource). The total volume of the identified Mineral Resources has increased by 28% since the last Mineral Resource Estimate The total Mineral Resource Estimate is now 141 Mt at 59% Fe with deleterious elements within sales specifications.
Next Steps
The Company will now focus on upgrading the Inferred Resources at C3, C4, Joyners Find and Bowerbird to Indicated and Measured Mineral Resource status. This will involve approximately 15,000m of infill RC drilling that is due to commence as soon as Program of Works Approvals ("POW") have been obtained. The objective of this drilling program is to convert the Inferred Mineral Resources to Indicated and Measured Mineral Resources that will underpin Ore Reserve calculations as a prelude to an application for mining approvals.
Resource Details
GWR's Wiluna West resource is reported in the following categories:
- Inferred Resource 98 Mt at 58 % Fe
- Indicated Resource 42 Mt at 60 % Fe
- Measured Resource 1 Mt at 62 % Fe
- Total Resource 141 Mt at 59% Fe
Recent diamond drilling and down hole geophysical surveys have vastly improved the geological understanding of the deposits. Additional mineralisation has been identified at Wiluna West. Significantly, the total volume of the identified Mineral Resource has increased by 9,270,000 m³ (28%) since the last Mineral Resource update, and a significantly larger portion of the Mineral Resources report above a 55% Fe cut-off. Offsetting this increase is a decrease in the density factor to better reflect the various mineralisation types. This adjustment in density led to tonnage loss of approximately 14% from previous Mineral Resource estimates.
The Mineral Resources are summarised in the table below. Snowden Mining Industry Consultants (Snowden) and Optiro Pty Ltd (Optiro) were commissioned to complete all of the block modelled Mineral Resource estimates. All sectional Mineral Resource Estimates have been calculated internally by GWR, but only represent 7% of the total reported Mineral Resource. All of the Mineral Resource estimates by Snowden have previously been announced. Resource Estimates undertaken by Optiro have not been previously announced and a Declaration and Statement of Consent from Optiro is appended to this announcement.
| Classification | Deposit | Calc | Tonnes (Mt) | Fe (%) | P (%) | Al2O3 (%) | Si02 (%) | LOI (%) |
|---|---|---|---|---|---|---|---|---|
| Measured | Bowerbird Central | Optiro 2009 | 1.16 | 61.89 | 0.037 | 2.89 | 6.53 | 1.68 |
| Total | 1.16 | 61.89 | 0.037 | 2.89 | 6.53 | 1.68 | ||
| Indicated | Bowerbird Central | Optiro 2009 | 5.42 | 58.15 | 0.056 | 3.86 | 9.67 | 2.85 |
| Bowerbird South | Optiro 2009 | 10.50 | 58.21 | 0.058 | 3.62 | 9.18 | 3.37 | |
| Jindalee Joyners | Optiro 2009 | 3.10 | 60.05 | 0.049 | 2.71 | 7.11 | 2.48 | |
| C3 | Optiro 2009 | 10.40 | 59.10 | 0.075 | 2.27 | 7.57 | 5.26 | |
| C4 | Optiro 2009 | 13.00 | 61.80 | 0.034 | 1.93 | 7.06 | 2.38 | |
| Total | 42.42 | 59.66 | 0.05 | 2.74 | 8.05 | 3.40 | ||
| Inferred | Bowerbird Nth Nth | GWR 2009 | 2.58 | 60.84 | 0.050 | 2.19 | 5.19 | 3.64 |
| Bowerbird Nth | Snowden 2008 | 3.90 | 59.70 | 0.040 | 3.80 | 6.50 | 2.60 | |
| Bowerbird Central | Optiro 2009 | 4.70 | 57.11 | 0.055 | 3.67 | 11.25 | 2.84 | |
| Bowerbird South | Optiro 2009 | 18.50 | 56.25 | 0.045 | 3.90 | 11.47 | 3.44 | |
| Joyner Find | Optiro 2009 | 4.00 | 64.90 | 0.015 | 1.87 | 2.90 | 1.96 | |
| Jindalee Joyners | Optiro 2009 | 5.10 | 60.17 | 0.026 | 2.81 | 7.31 | 2.08 | |
| C1 | Snowden 2007 | 4.20 | 58.50 | 0.088 | 3.30 | 7.20 | 5.20 | |
| C2 | GWR 2009 | 6.76 | 58.52 | 0.036 | 2.86 | 6.89 | 6.25 | |
| C3 | Optiro 2009 | 27.60 | 58.00 | 0.081 | 2.49 | 8.82 | 5.28 | |
| C4 | Optiro 2009 | 9.60 | 58.10 | 0.035 | 2.50 | 11.05 | 2.88 | |
| C5 | Snowden 2007 | 4.40 | 59.10 | 0.118 | 2.10 | 8.90 | 3.80 | |
| CR | Snowden 2007 | 4.00 | 60.60 | 0.030 | 1.40 | 9.30 | 1.70 | |
| South 2 | Snowden 2008 | 2.20 | 56.20 | 0.077 | 2.03 | 9.10 | 7.80 | |
| Total | 97.54 | 58.35 | 0.06 | 2.84 | 8.97 | 4.03 | ||
| Deposit Totals | Bowerbird Nth Nth | GWR 2009 | 2.6 | 60.84 | 0.050 | 2.19 | 5.19 | 3.64 |
| Bowerbird Nth | Snowden 2008 | 3.9 | 59.70 | 0.040 | 3.80 | 6.50 | 2.60 | |
| Bowerbird Central | Optiro 2009 | 11.3 | 58.10 | 0.054 | 3.68 | 10.01 | 2.73 | |
| Bowerbird South | Optiro 2009 | 29.0 | 56.96 | 0.050 | 3.80 | 10.64 | 3.42 | |
| Joyner Find | Optiro 2009 | 4.0 | 64.90 | 0.015 | 1.87 | 2.90 | 1.96 | |
| Jindalee Joyners | Optiro 2009 | 8.2 | 60.12 | 0.035 | 2.77 | 7.23 | 2.23 | |
| C1 | Snowden 2007 | 4.2 | 58.50 | 0.088 | 3.30 | 7.20 | 5.20 | |
| C2 | GWR 2009 | 6.8 | 58.52 | 0.036 | 2.86 | 6.89 | 6.25 | |
| C3 | Optiro 2009 | 38.0 | 58.30 | 0.079 | 2.43 | 8.48 | 5.27 | |
| C4 | Optiro 2009 | 22.6 | 60.23 | 0.034 | 2.17 | 8.75 | 2.59 | |
| C5 | Snowden 2007 | 4.4 | 59.10 | 0.118 | 2.10 | 8.90 | 3.80 | |
| CR | Snowden 2007 | 4.0 | 60.60 | 0.030 | 1.40 | 9.30 | 1.70 | |
| South 2 | Snowden 2008 | 2.2 | 56.20 | 0.077 | 2.03 | 9.10 | 7.80 | |
| Grand Total | 141.1 | 58.77 | 0.06 | 2.81 | 8.67 | 3.82 |
For full release and competency notes, download: Wiluna West Hematite Resource Upgrade (26 October 2009) (PDF, 965 KB)