Resolution Minerals Ltd (ASX:RML, OTC:RLMLF, FRA:NC3) has hit broad, near-surface gold mineralisation in two of three diamond holes drilled at the southern end of the Golden Gate Fault Zone at its 100%-owned Horse Heaven gold-antimony-tungsten-silver project in Idaho, with all holes ending in mineralisation.
The company said the results support a new gold discovery at Golden Gate South, extending the Golden Gate system beyond the initial discovery at Golden Gate North.
The maiden 2025 Horse Heaven drilling included 3 diamond core holes at Golden Gate South for 887 metres. Holes HH-GG25-008C and HH-GG25-010C tested gold anomalies identified in surface rock samples from a vein system along the Golden Gate access road, linked to a CSAMT geophysical anomaly. Hole HH-GG25-009C followed up historic intercepts from holes 87-GGR-4, 87-GGR-10 and 87-GGR-45, also associated with a low-resistivity CSAMT anomaly.
Key intercepts reported were:
- HH-GG25-009C: 172.2 metres @ 0.464 grams per tonne (g/t) Au, including 27.6 metres @ 0.89 g/t Au, with a best interval of 3.3 g/t over 1.5 metres; hole ended in mineralisation
- HH-GG25-010C: 225.5 metres @ 0.14 g/t Au from surface to end of hole
- HH-GG25-008C: anomalous mineralisation through the hole, ending in mineralisation grading 0.91 g/t Au
The holes ending in mineralisation suggest potential for extensions at depth, while near-surface tungsten was intersected in multiple shallow veins, pointing to additional multi-commodity upside.
The company’s first significant near-surface discovery at Golden Gate North included 189.2 metres @ 1.3 g/t Au (HH-GG25-001C) and 253 metres @ 1.5 g/t Au (HH-GG25-003C), with mineralisation also open at depth.
Drill hole parameters of holes subject of this announcement, HH-GG25-008C, HH-GG25-008C, HH-GG25-008C (highlighted), and of drillholes already released to the market.
With Golden Gate South now added, Resolution said mineralisation along Golden Gate North and South extends over about 1.5 kilometres of strike. Horse Heaven sits in Idaho and is immediately adjacent to Perpetua Resources’ Stibnite gold project.
“The discovery at Golden Gate South materially expands the Golden Gate gold system and confirms the presence of multiple mineralised shear zones over a substantial strike length,” RML’s CEO of US Operations, Craig Lindsay, said.
“With mineralisation open in all directions and drilling returning broad, near-surface intercepts, Golden Gate is rapidly emerging as a highly significant gold discovery. The interval lengths and grades on holes assayed to date, and the fact that mineralisation continues over such a long strike length, make us very excited to continue drilling here and target establishment of a maiden JORC compliant mineral resource.”
Upscaled drilling planned as Golden Gate footprint expands
Resolution’s diamond hole HH-GG25-009C has confirmed broad, intermittent gold mineralisation at Golden Gate South, with mineralisation present through to the end of hole and considered open at depth.
The hole was collared about 200 metres south of historical shallow drilling that returned anomalous gold in pre-RML holes 87-GGR-43 to 45, and Resolution said mineralisation styles mirror those seen at Golden Gate North.
Resolution described the gold in HH-GG25-009C as associated with disseminated pyrite, plus quartz vein-hosted pyrite and arsenopyrite within sericite- to chlorite-altered monzonite and volcanic rocks.
The company believes the mineralisation relates to a steep, east-dipping sulphide-bearing shear zone around 500 metres east of the main Golden Gate gold-bearing shear that hosts Golden Gate North. This interpretation supports a second, parallel northeast–southwest trending structure — the Vibika Shear Zone — where rock chip sampling from the Vibika adits and southern Golden Gate hill suggests mineralisation could extend over about 3 km of strike.
HH-GG25-010C
At HH-GG25-010C, Resolution targeted north-striking quartz veining and silicification along strike from the historical Copper Cliff prospect and intersected gold mineralisation through the full length of the hole, alongside intermittent silver and pervasive low-level tungsten mineralisation. The hole also ended in mineralisation, leaving the system open-ended.
Resolution noted HH-GG25-010C intersected three narrow veins of strong tungsten mineralisation at shallow depths, with tungsten associated with Au-Ag-Sb mineralisation, though regional evidence suggests tungsten may occur as a distinct phase.
Cross section of drill hole HH-GG25-010C.
HH-GG25-008C
Meanwhile, HH-GG25-008C was drilled westward to test the eastern extension of the Golden Gate Shear Zone and returned broad intervals of anomalous gold across the hole, with both gold mineralisation and arsenic increasing with depth. Resolution said grades appeared consistently stronger below 1,000 feet downhole and the hole ended in mineralisation grading 0.91 g/t Au, the highest value recorded in the hole, again pointing to depth potential.
Cross section of drill hole HH-GG25-008C.
Follow-up drilling from new spur roads further west is planned to better intersect the principal Golden Gate shear zone mineralised corridor.
What’s next
Looking ahead, Resolution said Golden Gate — now comprising the Golden Gate North deposit and the emerging Golden Gate South prospect — is shaping as a significant near-surface gold discovery, with combined mineralisation extending around 1.5 kilometres along a northeast–southwest trend and remaining open along strike and at depth. It also flagged potential lateral repeats across strike, supported by repeating northeast–southwest faults that juxtapose Golden Gate North and South.
Resolution expects assays for HH-GG25-006C and the 3 reverse circulation holes drilled late in the 2025 season at Golden Gate North to be released once available, and said it is planning an upscaled drill campaign at Golden Gate from as early as May, focused on expanding both North and South discoveries.
RML expects to be in a position to commission a maiden JORC mineral resource estimate at Golden Gate North after completing the planned 2026 drill program. It also plans tungsten-focused drilling near the historic Golden Gate Tungsten Mine (last operated in 1980) and further south along the Golden Gate Fault where soil sampling has outlined a tungsten anomaly.
All 2026 drilling will be conducted under an existing drill permit, while a new exploration permit is being pursued to broaden the footprint and enable drilling across a much larger area using new roads and reopened closed roads. The company has also submitted samples from the 2026 Golden Gate drilling for initial metallurgical testwork.