Cardero Resource Corp. reports that it has confirmed the presence of gold and silver at the Zonia Copper Project, in Arizona. The Company assayed 11 drill samples from the Project and fire assay results indicate gold is present in all samples.
“As far as we know, none of the previous operators at Zonia took the important step of testing for gold mineralization as their focus was soluble copper for heap leaching,” stated Henk van Alphen, Cardero’s President & CEO, “The sulphide mineralization underlying the Zonia copper-oxide deposit has not been extensively drilled as yet, but every sample we tested returned a gold credit. The near-surface copper-oxide resource at Zonia remains our primary development focus, and it is early days in terms of defining pervasive gold and copper mineralization below it. However, the presence of potentially significant copper and gold mineralization underlying the resource will likely be helpful as we move forward.”
Details of Sampling Results
Historical drill samples at Zonia have only been analyzed for copper as almost all holes terminate within the upper oxidized zone. Only the last couple drill programmes were deep enough to intersect primary sulphides, with several drill holes extending below the copper-oxide resource and intersect underlying copper-sulphide mineralization. Cardero decided to test the idea that the underlying sulphide mineralization had potential to host significant gold grades and reject pulp samples from storage were selected across a range of copper grades. Eleven samples were taken from drill holes extending below the currently defined resource (Table 1). The locations of primary sulphide samples that were collected for analysis are shown on Figure 1 and Figure 2. All samples returned significant gold values, and the average gold:copper ratio is 0.45.
Next Steps
There are approximately 855 sample intervals underlying the existing copper-oxide resource that have been analyzed for copper, and which could now be analyzed for gold and silver, allowing the Company to calculate copper equivalent grades for the sulphide mineralization. Ultimately though, additional drilling will need to be completed to outline the extent of sulphide mineralization.
| Drill Hole |
From (ft) |
To (ft) |
Width (ft) |
Gold (g/t) |
Silver (g/t) |
Total Copper (%) |
Copper Equivalent (%) |
|---|---|---|---|---|---|---|---|
| RRC-10-CC | 580 | 585 | 5 | 0.584 | 3.8 | 0.68 | 1.21 |
| RRC-10-EE | 365 | 370 | 5 | 0.258 | 2.1 | 0.70 | 0.94 |
| RRC-10-EE | 395 | 400 | 5 | 0.638 | 3.4 | 1.09 | 1.66 |
| RRC-10-EE | 570 | 575 | 5 | 0.174 | 1.4 | 0.39 | 0.55 |
| RRC-10-HH | 620 | 625 | 5 | 0.116 | 1.3 | 0.34 | 0.45 |
| RRC-10-21 | 787 | 794.5 | 7.5 | 0.176 | 3.4 | 0.32 | 0.50 |
| RRC-10-22 | 851 | 860 | 9 | 0.084 | 2.6 | 0.33 | 0.43 |
| RRC-10-35 | 505 | 510 | 5 | 0.035 | 2.5 | 0.29 | 0.34 |
| RRC-10-28 | 520 | 525 | 5 | 0.117 | 2.6 | 0.40 | 0.52 |
| RRC-10-26 | 300 | 305 | 5 | 0.055 | 1.8 | 0.30 | 0.36 |
| RRC-10-J1 | 410 | 415 | 5 | 0.048 | 2.7 | 0.33 | 0.39 |
Copper Equivalent calculations use metal prices assumptions of $2.20/lb for copper, $1200/oz for gold, and $15/oz for silver. Copper equivalent calculations reflect gross metal content and have not been adjusted for metallurgical recoveries.