Exploration pitting works at Xtract Resources’ Eureka copper/gold deposit, in Zambia, have confirmed earlier modelling of a strike extension to the northwest.
Earlier three-dimensional modelling on the Eureka main pit copper/gold deposit suggested that the mineralisation might extend towards the west-northwest from the small historic openpit, along the trend of a 3 km copper-in-soil anomaly.
A programme of exploration pitting was undertaken by the company to test for such extensions.
The pitting programme is designed to track extensions to the Eureka copper/gold deposit on small-scale mining licence number 22134-HQ-SML, located in the central part of Zambia.
A total of 19 pits were dug by mechanical excavator at 50 m spacing along north-south profiles to a maximum depth of 7 m, chiefly on the main Eureka openpit extension, but also including several in the area of the ‘villager’s pit’ on the Eureka West target.
The pit channel sample measurements, which were conducted by a hand-held X-ray fluorescence analyser, returned values in weathered bedrock up to 2.65% copper in pit EX-P3.
As such, Xtract believes there is potential to extend the deposit strike by more than 50% to over 300 m. In this regard, the zone potentially remains open to further strike expansion beyond the exploration pitting area and is open down-plunge.
In addition, pitting at Eureka West indicates potential for additional width at this target.
Going forward, Xtract is planning to undertake follow-up drilling with the aim of significantly expanding the Eureka deposit.
Xtract executive chairperson Colin Bird says this exploration pitting programme has produced a pleasing result, with high grade sample results in pits EX-P1 to EX-P4 to the northwest of the historic openpit confirming historic copper soil anomalies on the axis of the previously established mineralisation.
“The programme certainly gives us confidence regarding our immediate goal of a small-scale copper-producing operation. The system is open ended, and there is potential to identify a larger discovery.”
He says Xtract’s intention is now to prepare for a drill programme to identify a mineral deposit of sufficient capacity to support a seven-year openpit mine life, whilst drilling outlying holes to test for more significant extensions.
The weathering profile in the vicinity of the main Eureka openpit is quite deep and most of the exploration pits did not encounter solid bedrock, mainly cutting through overlying soils and saprolite. Channel profile samples were taken every metre down the pits and these were subsequently dried, sieved, labelled and bagged in the field for later analysis.
Prepared samples were analysed for copper by Lusaka-based independent geological contracting company GeoQuest.