Round 14 Geophysics and Drilling Collaboration Program Preliminary Report Border Gold Target Testing Lake Mackay Project EL 25146 and EL 31234

Abstract

IGO Limited (IGO) received co-funding support for drilling in the southwestern Aileron Province of central Australia during Round 14 of the Northern Territory Government's Geophysics and Drilling Collaborations (GDC) Program. This final report details the reverse circulation (RC) drill program that tested three gold-in-soil targets in tenements EL 31234 and EL 25146. The tenements are part of the Lake Mackay joint-venture project between IGO and Prodigy Gold NL (PRX). The co-funded program involved the drilling of 10 RC holes, four on EL 25146 and six on EL 31234, for a total of 1,344 metres. The drilling was completed between the 16th and 29th of May 2022, operated by joint-venture partner PRX. The drill areas are located nearby to two gold prospects recently discovered by IGO: the Arcee prospect discovered in 2019, approx 9 km southwest, and the Goldbug prospect discovered in 2020, approx 45 km east, of the drill targets. The new drilling tested at depth beneath three coherent gold-in-soil anomalies generated using 3 phases of 50 micrometre BLEG soil sampling. The targets had comparable gold-in-soil anomalies to those that led to the discovery of the Arcee and Goldbug prospects. Drill holes SGRC2207 and SGRC2208 intersected intervals of low-grade gold mineralisation associated with base metal sulfides between 84-100 m depth. The best interval in hole SGRC2207 intercepted 16 m at 0.4 g/t Au from 84 m, including 4 m at 0.5 g/t Au, 0.5% Cu and 2.8 g/t Ag from 84 m. The mineralisation occurred at the contact between a poorly understood diorite intrusion, and metamafic sills of the Du Faur Suite, that are hosted within metasedimentary schist of the Lander Rock Formation. The polymetallic mineralisation is sub-economic, but follow-up drilling should be considered. Other drill holes in the program intercepted minor sulfide mineralisation including pyrite, pyrrhotite and arsenopyrite, however no significant gold or base metal mineralisation was returned.