Idaho Operations First Drilling And Resource Expansion Program

AUSTRALIA - Jervois Global Limited reported on in-fill drilling and first resource expansion drilling program at its Idaho Cobalt Operations (ICO) in Idaho. The 2022 drilling program at ICO totaled 10,300 meters (m) in 69 completed diamond drillholes.  With the exception of a single geotechnical drillhole, the 2022 drilling was focused on the RAM deposit underpinning current mine development at ICO, and its down-dip extents, and comprised 62 infill drillholes (totaling 7,730m) and 6 targeted RAM resource expansion drillholes (totaling 2,300m).

In-fill drilling confirmed the current RAM deposit resource model and continues to de-risk mining.  In conjunction with other technologies being utilized at ICO, including Exyn autonomous drone lidar survey systems, in-fill drilling is a key component that will better enable the ICO team to forecast and manage grade control and dilution.  

During 2022, Jervois completed 62 in-fill drill holes with all of the holes targeting and intersecting the Main Mineralized Horizon (MMH) of the RAM deposit.  The RAM deposit is defined by a Mineral Reserve and Resource Estimate (MRRE), which was calculated in accordance with standards set forth in both the Australasian JORC Code 2012 (JORC) and by the Canadian Institute of Mining (CIM).  In total, Jervois has now drilled 81 drill holes targeting the MMH of the RAM deposit since acquiring the project in mid-2019 (including 19 holes completed in late 2019), with all holes intersecting mineralization.  This represents an increase of over 80 percent with respect to the total number of resource drillholes defining the RAM deposit prior to Jervois ownership; a step change in orebody delineation and derisking of the mine plan.

Most importantly, in-fill drilling results to date demonstrate the validity of the ICO MRRE, particularly in and around underground areas that have recently been opened for early mine production and development.  Furthermore, during 2022 mine development work within the hanging wall of the RAM deposit, several areas comprising “waste” blocks within the current MRRE were found to be mineralized and this material has been stored for processing during plant commissioning.

In-fill drilling is ongoing and will continue through 2023 as vertical mine development progresses, focused on production areas within the upper levels of the Mid Zone and the South Zone of the deposit.

Jervois’ resource expansion drilling program targeted down-dip extensions of the RAM deposit initially from surface and then from underground platforms as mine access was established.  Six (6) expansion drill holes were completed in 2022, with assays recently returned from one surface and one underground hole.  Assays from the remaining four holes are expected later this quarter.  Massive and disseminated cobalt-copper sulphide mineralization was observed (logged) in all six (6) expansion holes, which was confirmed by pXRF testing.  While assays for four of the six expansion holes are still pending, these results confirm down-dip mineralization continuity in the RAM deposit in both the south and mid zones.

Drill results to date include: Hole JS22-001B collared from surface intersected 0.58% Co, 0.66% Cu, 0.31 g/t Au over a calculated true width (CTW) of 6.0m, including 1.06m CTW at 1.71% Co, 0.70% Cu, 0.75 g/t Au; and Hole JU22-064 collared from an underground platform intersected 0.27% Co, 0.67% Cu, 0.14 g/t Au, over a calculated true width of 2.4m.

Drilling from underground platforms has confirmed broad mineralization continuity over more than 260m laterally and 180m vertically beneath the southern resource zone. Drilling conducted from surface has increased resource confidence at the base of the northern resource zone. The results continue to provide confidence that the RAM resource will ultimately support extended mine life at ICO beyond the initial seven years, as discussed within the project’s Bankable Feasibility Study (BFS) released in 2020 and introduces the potential for higher annual production rates1.  The RAM deposit remains open at depth and along strike, and Jervois is confident that there is significant potential of both resource and reserve expansion.  Jervois expects to complete an updated JORC and CIM National Instrument (NI) 43-101 compliant MRRE in Q2 2023.  The updated ICO MRRE will be used to update production block models for mine plans across multiple time horizons.