Carnaby Resources Limited (ASX: CNB) has obtained “exceptional” new exploration results at the Greater Duchess Copper-Gold Project in Mt Isa, Queensland. These include an exciting new high-grade discovery at Duchess.
“At Duchess, while it is early days, the new high-grade discovery is encouraging as it lies immediately west of the extremely high-grade Duchess Mine Lode which averaged 12.5% copper at the turn of the century and was one of the main copper mines in the Mount Isa district from circa 1900-1930,” Managing Director, Rob Watkins, said.
“Mount Hope Central continues to impress with exceptional new drill results from outside of the existing Mineral Resource and new targets generated from a recent drone survey. Plans are afoot for a major drilling program to commence soon.”
A single RC drill hole was completed at Duchess at the end of 2024 targeting an off hole conductor from a previous downhole EM survey in the area. This new hole DCRC006 has intersected a high-grade discovery on the Duchess Central Lode immediately west of the extremely high grade Duchess Mine Lode which averaged 12.5% copper at the turn of the century and was one of the main copper mines in the entire Mount Isa district from circa 1900-1930.
The result in DCRC006 of 4m @ 7.0% Cu, 0.05g/t Au from 149m within 10m @ 3.3% Cu, 0.1g/t Au from 146m is located on the Duchess Central Lode and is completely open at depth.
The Duchess Central Lode is located immediately east of the Ivanhoe Lode which itself has only been drilled to very shallow depths in mostly single hole traverses. The Ivanhoe Lode has a Mineral Resource of 3.7Mt @ 0.7% Cu, 0.1g/t Au.
Only seven historical RC holes have been drilled targeting the Duchess Central Lode over a strike length of 200m, with all holes intersecting the Central Lode less than 100m from surface.
While it is early days, the new high-grade discovery represents one of the most significant drill results recorded in the Duchess area and is highly encouraging given the close proximity to the main historical high grade Duchess Mine Lode, which had an average head grade of 12.5% Cu. Further drilling is required to determine if the new high-grade discovery on the Central Lode is continuous at depth and along strike.
Drone survey
A very detailed drone magnetic survey has been completed over the entire Mount Hope Mining Lease at 20m line spacings. No detailed magnetic surveys have previously been recorded over Mount Hope.
The drone survey has highlighted several new untested magnetic high targets which are being evaluated prior to drill testing. The magnetic highs are likely a direct result of magnetite or pyrrhotite alteration and mineralisation. Magnetite is consistently seen as strong but discrete alteration over several meters into the hangingwall and footwall to the Mount Hope Lodes. Magnetite alteration is also present as an accessory mineral throughout the lodes at Mount Hope especially in the Chalcus Lode. Pyrrhotite mineralisation is also strong within the Mount Hope Lodes with up to several percent in places.
Therefore, the new magnetic high targets identified could be a direct vector towards copper gold mineralisation and will form an important targeting tool for ongoing exploration.
While magnetite and pyrrhotite are considered key accessory minerals of the Mount Hope ores, it should be noted that they can and do precipitate independently from the copper gold chalcopyrite mineralisation, often forming haloes and therefore are only a guide to the location of active IOCG fluid pathways.
