Castillo Copper Ltd (LSE:CCZ, FRA:7OR, ASX:CCZ) has hit further high-grade copper in its second drilling campaign at the Big One Deposit at Mt Oxide Project within the Mt Isa copper-belt in Northwest Queensland.
The drill program was designed to extend known mineralisation and test the halo south of the dacite dyke.
Importantly, the first four drill holes extended known mineralisation, as they were proximal to the dacite dyke, with best intersections of:
- 9 metres at 1.42% copper from 88 metres, including 4 metres at 3.06% copper from 92 metres and 1-metre at 9.19% copper from 92 metres;
- 5 metres at 1.06% copper from 141 metres;
- 16 metres at 0.59% copper from 166 metres, including 3 metres at 1.76% copper from 176 metres; and
- 3 metres at 1.22% copper from 65 metres.
“High-grade mineralisation extended”
Castillo Mt Oxide Project tenements.
Castillo managing director Simon Paull said: “With results in from the second drilling campaign, it’s encouraging that high-grade mineralisation was extended.
“Moving forward, the third drilling campaign at Big One Deposit will hit priority targets north of the line of lode, which includes a sizeable bedrock conductor.
“In the interim, however, the board is looking forward to work finally commencing at the Arya Prospect and results of the due diligence programme which is continuing on the Litchfield & Picasso lithium projects.”
Campaign overview
Big One Deposit – Drill holes along the line of lode.
Castillo’s drill campaign comprised 20 reverse circulation (RC) holes totalling 2,632 metres and one with an HQ diameter diamond-core tail for a total of 32 metres.
Promisingly, the findings are consistent with the geology team’s expectations and their understanding of the underlying system.
These intersections are broadly in line with results achieved from the inaugural drilling campaign undertaken in late 2020, which comprised:
- 40 metres at 1.64% copper from surface, including 11 metres at 4.40% copper from 24 metres, 5 metres at 7.34% copper from 28 metres and 1-metre at 16.65% copper from 29 metres; and
- 44 metres at 1.19% copper from surface, including 14 metres at 3.55% copper from 27 metres, 3 metres at 10.88% copper from 37 metres and 1-metre at 12.6% copper from 37 metres.
Furthermore, the drill holes that targeted the halo, south of the dacite dyke, verified the known system runs for only about 400 metres along the strike extent then intersects at a sharp angle with a major regional fault.
Third drilling campaign
Castillo has formulated a third drilling campaign comprising at least 22 drill holes targeting several prime areas.
The company’s drilling will target areas on the northern side of the dacite dyke, including a sizeable bedrock conductor identified during the induced polarisation campaign.
Importantly, the geophysical characteristics of the northern bedrock conductor are identical to the anomaly along the line of lode where known mineralisation has been discovered.
High-grade stockpiles
High-grade stockpiles at Big One.
As part of the exploration program across the Big One Deposit, sampling occurred at 12 separate legacy stockpiles from mid-1990 mining operations.
Accurate volumes were calculated from a drone survey, which assessed the stockpiles to comprise 7,407 tonnes at 1.17% copper.
Based on sample rock chips taken from the stockpiles, the assays returned up to 3.32% copper reconfirming the high-grade nature of the underlying system.
However, there will need to be further metallurgical testing and a mining lease secured to process the stockpiles.
Next steps
At the Arya prospect, the logistics team are on-site, preparing the helipad/drill pads, getting ready for the equipment to arrive.
For the lithium projects, due diligence is progressing on the Litchfield and Picasso projects.
At Zambia, Castillo plans to complete an IP survey at the Luanshya & Mkushi projects then analyse the results for incremental targets for test-drilling.
Furthermore, the company aims to begin work on the inaugural drilling campaign for the Luanshya Project.