- Encouraging preliminary results from the drilling campaign, underway at the Big One Deposit, delivered the following:
- Factoring in results from the recent Induced Polarisation (IP) survey, the first three drill-holes, BO_315RC-17RC, proximal to BO_2020_201RC-03RC1, all intercepted mineralisation (Figure 1) based on the field geologist’s estimates
FIGURE 1: BEST INTERCEPTED MINERALISATION
| Borehole | From (m) | To (m) | Apparent Thickness (m) | ||||||||||||
| BO_315RC : | 61.0 | 69.0 | 8.0
| BO_316RC : |
113.0 | 120.0 | 7.0
| BO_316RC : |
129.0 | 146.0 | 17.5
| BO_317RC : |
90.5 | 103.0 | 12.5 |
|
- Compared to drill-holes 201RC-03RC (1) from the 2020 campaign, 315RC-317RC were drilled deeper, intersecting mineralisation within and external to the trachyte dyke:
- This is significant, as it supports interpretations from the recent IP survey that copper mineralisation is controlled by major structural trends rather than constrained purely within the trachyte dyke
- More significantly, fresh interpretations from the preliminary observations verify that known mineralisation has clearly been extended – further insights will become apparent once assays, under fast-track request, are returned from the laboratory
- With 23 drill-holes still to complete, considerable exploration potential remains over the balance of the campaign, which has so far effectively demonstrated that leveraging IP survey findings better targets underlying mineralisation
- Preliminary findings from DHEM surveys undertaken on 315RC-317RC and eight drill-holes from the 2020 campaign (1) suggest the density of copper mineralisation intersected is potentially higher than initially envisaged:
- Subject to a full analysis by the geophysics team, however, the initial interpretation is further verification of extensions to known mineralisation
Castillo Copper’s Managing Director Simon Paull commented: “Factoring in the IP survey results to our re-designed drilling campaign at the Big One Deposit has delivered excellent initial results, with significant mineralisation intersected. Moreover, the DHEM survey results now suggest the density of the underlying copper mineralisation is greater than the Board initially expected. Holistically, the Board is delighted with these early results, as our core goal over the course of the campaign is to significantly extend known mineralisation.”
Castillo Copper Limited (“CCZ”) is delighted to report that mineralisation was intersected in the first three drill-holes (BO_315RC-17RC) at the Big One Deposit, within the Mt Oxide project (Appendix A).
According to the field geologist’s estimates, the intercepts ranged from 7-17.5m over the three drill-holes; the cumulative size of the intercepts ranged from 14-24.5m. In addition, preliminary DHEM survey results from BO_315RC-17RC and eight 2020 drill-holes (1) suggest the density of copper mineralisation intersected is potentially higher than initial expectations.
ENCOURAGING INITIAL RESULTS
Insights from preliminary drilling
After analysing findings from the recent IP survey, the drilling campaign for the Big One Deposit was redesigned to improve the prospects of hitting underlying copper mineralisation. The initial three drill-holes (BO_315RC-17RC), which are proximal to BO_2020_201RC-03RC (1) from last year’s campaign, all intersected mineralisation, ranging from 7-17.5m, based on estimates from the field geologist (Figure 2 and Appendix B).
Notably, compared to 201RC-03RC (1) from the 2020 campaign, 315RC-17RC were all drilled deeper resulting in them intersecting mineralisation within and external to the trachyte dyke. This is significant since it supports interpretations from the IP survey that copper mineralisation is structurally controlled, rather than constrained within the trachyte dyke.
Based on early interpretations, the new drill results clearly extend known mineralisation though proper insights will not be forthcoming until the assays are returned and thoroughly analysed by the geology team.
Nevertheless, with 23 drill-holes remaining to be completed on the current campaign, the Big One Deposit continues to deliver significant exploration potential.
FIGURE 2: BIG ONE DEPOSIT – QUALITATIVE ASSESSMENT OF DRILLHOLES 315RC-317RC (
| Borehole | From (m) | To (m) | Apparent Thickness (m) | Comments | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| BO_315RC: | 58.0 | 61.0 | 2.0 | Dacitic
| BO_315RC: |
61.0 | 69.0 | 8.0 | Dacitic, pervasive orthoclase
| BO_315RC: |
69.0 | 71.0 | 2.0 | Dacitic, some orthoclase
| BO_316RC : |
113.0 | 120.0 | 7.0 | Quartzite
| BO_316RC : |
129.0 | 146.5 | 17.5 | Fractured quartzite
| BO_317RC: |
11.0 | 13.0 | 2.0 | Dacite
| BO_317RC: |
20.0 | 24.0 | 1.0 | Dacite
| BO_317RC: |
42.0 | 43.0 | 1.0 | Dacitic
| BO_317RC: |
65.0 | 66.0 | 1.0 | Dacite
| BO_317RC: |
75.0 | 76.0 | 1.0 | Dacite
| BO_317RC: |
90.5 | 103.0 | 12.5 | Dacite
| BO_317RC: |
103.0 | 105.0 | 2.0 | Quartzite |
|
Notes:
- Samples have been taken at 1m intervals;
- Mineralisation estimated from field geologists rock-chip estimates;
- True vertical depths will be calculated by Minescape block model procedures;
- A zone of limited mineralisation inferred to be associated with the dyke was intersected in each deepened drill hole; and,
- In borehole BO_317RC, the dyke was intersected at a shallower depth than predicted; hence, there was no requirement to drill the bore to the estimated total depth of 150m.
Source: CCZ geology team
Indicative DHEM survey findings
DHEM surveys were conducted on eight mineralised drill-holes from the 2020 campaign1 and 315RC317RC. A more detailed analysis on BO_301RC, which focused on copper mineralisation between 24-42m, verified the density was much higher than initially envisaged. This is a major fundamental finding as clearly higher density implies the potential for significant incremental extensions to known copper mineralisation. However, a full interpretation will not be forthcoming for several weeks, as the geophysics team need to complete the campaign then thoroughly analyse the findings.
PHOTO GALLERY – DRILLING TEAM AT BIG ONE DEPOSIT
Source: CCZ geology team [Location: 7,880,306E, 335,422N]
Next steps
There are several ongoing steps, including:
- Continuation of the drilling campaign at Big One Deposit, complemented by further progress reports and interpretations of assay results.
- Finalise logistics for the drilling campaign at the Arya and Sansa Prospects.
- Identifying the next target to drill post work at the Arya and Sansa Prospects.
References
- CCZ ASX Release – 11 January 2021