JERVOIS PROJECT OVERVIEW | DEVELOPMENT & PERMITTING | OTHER PROSPECTS
Geology
The Jervois Project is located on four Mineral Licences (ML 30180, ML 30182, ML 30829 and ML 32277) located within EL 25429 held by Jinka Minerals, a subsidiary of KGL Resources.
Base metal mineralisation at Jervois is hosted by a lower-to-middle amphibolite grade metasedimentary sequence of the Bonya Metamorphics. The Bonya Metamorphics is a unit in the Aileron Province of the Palaeoproterozoic eastern Arunta Region that reached peak metamorphism during the regionally extensive high-T low-P Strangways Event. The base metal mineralisation at Jervois is stratabound and contained within steeply dipping lenticular bodies (lodes) of calc-silicate, garnet-chlorite-magnetite rock and garnet-magnetite quartzite, within a thick succession of spotted andalusite-cordierite schist and quartz-sericite-magnetite schist. The mineralised sequence has a strike length of some 12km and a stratigraphic thickness up to about 600m.
Drilling at Rockface looking south towards the prominent ferruginous ridge
Resource
Mining Associates was commissioned by KGL to complete updated Mineral Resource estimates for the Reward, Bellbird and Rockface deposits forming the majority of the delinated Resource for the Jervois Copper Project. The target commodity is copper with subordinate silver, gold, lead and zinc.
Since acquiring Jervois in 2011, the copper mineral Resources have been significantly been upgraded at Jervois.
Confidence levels in the resource estimates have been strengthened, with 60% of the total copper mineral Resources in the Measured or Indicated category. The total copper resource estimates now stand at : -
23.8 million tonnes at 2.02% copper, 0.25 g/t gold and 25.3 g/t silver,
containing 481.2 kt copper and 19.35 million ounces silver, and 189,600 ounces of gold
The considerable advances in the resource base when compared with the previously reported estimate, are due to the confirmatory infill drilling undertaken from 2021 and 2022, coupled with improved understanding of the geological controls on mineralisation. This was achieved through the systematic incorporation of drill results in the geological models and adapting the drill plans accordingly.
Resources update in detail
The progress in upgrading of the mineral Resource at the Jervois Copper Project is shown below.
The latest Resource Estimates for the Reward, Rockface and Bellbird deposits are detailed below in Table 1.
Table 1- Jervois Copper Project Current Resources (Released to the ASX on 14/09/2022)
Improved Geological Model
During the last 5 years the KGL geology team has greatly improved the understanding of the controls of mineralisation and disposition of the mineralised lodes. As outlined in the August 2019 JORC report, improved field protocols, supplementing legacy core-logging codes, were introduced in 2017 for lithology, alteration, mineralisation and structures.
The result has greatly enhanced geological understanding and consistency in logging of lithology, alteration, mineralisation and structural domains and subgroups. KGL now recognise two main styles of mineralisation and alteration/metamorphic mineral assemblages:
1. Lower tenor, primary syn-depositional or stratabound disseminated sulphides and
2. Higher grade, structurally controlled shoots representing both remobilised stratabound syngenetic mineralisation, possibly related to late regional intrusion-related mineralising event.
Higher grade mineralised shoots are the result of reworked and remobilised primary strata-bound base metals during deformation. During late stage deformation regional-scale granite intrusions likely provided the heat and fluids that remobilised copper from primary (stratabound) units, into structural traps such as anticlinal fold hinges. The structural framework for this is supported by research of the Northern Territory Geological Survey (e.g. McGloin et al 2019 and Weisheit et al 2019). The shoots are observed as massive or semi-massive sulphidemagnetite veins and chalcopyrite-rich brecciated veins as shown in the image below.
The improved geological model, upon which this resource update is based, widens opportunities to target higher grade extensions and repetitions within favourable host rocks and structures in other areas adjacent to known deposits and in other prospects at Jervois and the surrounding Unca Creek tenement.
Jervois JORC Reports
View the latest Jervois JORC report (Bellbird) , released 14 Sep 2022.
View the latest Jervois JORC report (Rockface) , released 7 Mar 2022.
View the latest Jervois JORC report (Reward), released 10 Jan 2022.