Toronto, Ontario — December 18, 2025 — Leads & Copy — Omai Gold Mines Corp. has announced assay results from the second hole drilled on the Gilt Creek gold deposit at its 100%-owned Omai Gold Project in Guyana.
Hole 25ODD-122(w) drilled 708m of the Omai Stock, an intrusive rock unit that produced 2.4 million ounces of gold between 1993-2005 from the upper portion from surface to a vertical depth of approximately 250m, according to the company.
Hole 25ODD-122(w) was drilled from surface to a total depth of 2,014m with results previously reported for the lower part of the hole that confirmed the presence of the adjacent Wenot deposit at a depth of approximately 1,200m, or 700m below the known Wenot gold mineralization. The upper part of hole 122(w) was drilled from surface through a mafic volcanic sequence, then through the known diabase dike, and first intersected significant gold mineralization at a vertical depth of approximately 260m. Gold mineralization proved extensive throughout the Gilt Creek intrusion and extends into the surrounding volcanic rocks as well.
The Gilt Creek deposit is one of two orogenic gold deposits at the Omai Gold Project in Guyana. Hole 122w showed that the Wenot shear at this depth hosted seven significant gold zones (news release November 12, 2025).
A 708.1m interval in Hole 122(w) averaged 1.06 g/t Au with multiple intervals with higher grades. Highlighted higher grade zones from the upper part of hole 25ODD-122w include: 1.06 g/t Au over 708.1m (from 364.9) includes 1.78 g/t Au over 46.2m (from 635.6 downhole) includes 4.88 g/t Au over 7.0m (from 566.3m), 1.32 g/t Au over 99.2m (from 702.0m) includes 5.7 g/t Au over 8.0m (from 766.9m), 3.10 g/t Au over 24.0m (from 395.5m), 1.99 g/t Au over 32.0m (from 462.0m), 2.98 g/t Au over 17.8m (from 643.8m), 2.04 g/t Au over 43.2m (from 952.2m).
Mineralization in the Gilt Creek deposit first occurs just 46m downhole with 1.37 g/t Au over 7.5m in saprolite and ends at 2,014m with 3.61 g/t Au over 4.4m within less than 5m of the end of the hole in the adjacent Wenot deposit.
Elaine Ellingham, President & CEO, said the results from Hole 122 further confirm the extent of gold mineralization within and beyond the known deposit and show the robust and continuous nature of the gold-mineralized regime within the Gilt Creek quartz-diorite intrusive stock. She added that this new hole, together with the earlier hole 095, provide valuable structural data for rock mechanics and material for metallurgical sampling, both that allow the company to advance its mine plan for its upcoming updated Preliminary Economic Assessment that will include the Gilt Creek deposit.
According to the company, all samples >0.5 g/t Au were also assayed using a metallic screening process that provides a more representative total grade than fire-assay on a 50g sample alone.
The Gilt Creek orogenic gold deposit is located less than 500m north of the Wenot deposit, which has been the focus of most of the Company’s drilling and resource expansion.
Hole 25ODD-122(w) was collared on the northwest flank of the old Gilt Creek pit, also at the eastern end of the recently drilled near-surface BBH gold trend. The initial gold zone in hole 122 of 1.71 g/t Au over 6.0m occurs in saprolite within 40m of surface and is part of the BBH target area. Hole 122 then drilled through mafic volcanic rocks to a downhole depth of 299m where it intersected the well-known diabase dike, with a true thickness of approximately 138m. Hole 122 was wedged within the diabase dike in order to flatten it sufficiently to reach the ultimate projected target depth under Wenot for this hole. It continued as hole 122w.
Below the diabase dike but before drilling into the intrusive complex, both hole 095 and 122 drilled a small interval of the surrounding mafic volcanics. In hole 122w, a gold zone within the volcanics assayed 3.10 g/t Au over 24.0m. Similarly in hole 095 the volcanics hosted gold mineralization, with assays of 2.09 g/t Au over 10.5m and a second zone of 1.59 g/t Au over 7.5m.
The Gilt Creek intrusive complex was first intersected at 367.5m downhole, continuing to 1078.5m, a total of 711m, with gold mineralization throughout much of this. All 711m of the Gilt Creek Intrusive drill core was sampled and 226 of the 572 samples or 40% assayed greater than 0.5 g/t Au. Iamgold drilled approximately 27,000m in 46 holes in 2006-7 in this lower part of the Gilt Creek deposit and similarly had 41% of the samples assaying greater than 0.5 g/t Au. Hole 24ODD-095 also had 39% of Gilt Creek samples assaying over 0.5 g/t Au.
The Gilt Creek drill holes (24ODD-095 and 25ODD-122) achieve several objectives: assist in mine planning and metallurgical studies that will facilitate inclusion of Gilt Creek into an updated Preliminary Economic Assessment (PEA) mine plan expected in H1 2026, test and verify historical drilling and at the same time explore the lateral extent of gold mineralization beyond that previously identified, and assist in the geological modelling of the Gilt Creek deposit in order to assess the overall exploration potential and extent of this very large gold system on the broader Omai property.
To facilitate mine planning, a televiewer system surveyed hole 095 in early 2025, together with select holes at the Wenot deposit. This optical and acoustic system provides detailed in-situ mapping of all rock structures, giving quality data to guide mine design and assist in a greater understanding of the structural geology. Neither hole 122(w) nor hole 095 encountered any high pressure or noteworthy water return during drilling or televiewer surveying.
Hole 122 was designed to continue much further, to test the adjacent Wenot gold deposit that lies only 450m south of the Gilt Creek deposit. The hole reached an impressive downhole depth of 2,014m and was successful in encountering the Wenot shear corridor at 1,739m downhole. It continued through 275m of the shear corridor, still within the Wenot shear zone at the end of the hole and with significant mineralization of 3.61 g/t Au over 4.4m, including VG within 5m of the end of the hole. Seven significant gold zones were encountered in this depth extension of Wenot, at the bottom of this same hole 122(w).
By applying the same cut-off grade of 1.5 g/t Au as was used in the resource estimate, a cumulative 150.4m (not continuous) has a weighted average grade of 3.20 g/t Au, very similar to the resource grade. In hole 095, it was noted that 198.3m (not continuous) has a weighted-average grade of 2.78 g/t Au, both comparable with the resource grade.
The Gilt Creek gold deposit is a large 500m by 275m compact, intrusion-hosted orogenic gold deposit located approximately 500m north of the Wenot gold deposit on the Omai property. The Mineral Resource Estimate for Gilt Creek comprises Indicated Resources of 1,151,000 ounces gold averaging 3.22 g/t Au in 11.1 million tonnes and Inferred Resources of 665,000 ounces gold averaging 3.35 g/t Au in 6.2 Mt, using a 1.5 g/t Au cutoff and a US$1,700/oz gold price. Initial conceptual engineering studies anticipate a ramp from surface to access this deposit for underground mining.
The upper portion of this Gilt Creek gold deposit was open pit mined between 1993 and 2005, producing 2.4 million ounces averaging 1.5 g/t Au. Continuation of this deposit at depth was confirmed by IAMGOLD Corporation in 2006-2007 with 46 drill holes totalling approximately 27,000m. This drilling showed gold mineralization down to a depth of 967m below surface, although only sparse drilling was completed to that depth.
Approximately 80% of the Gilt Creek gold Mineral Resource Estimate is relatively shallow, lying at vertical depths of between 280m and 600m. Limited drilling of the Omai intrusion below 600m continues to encounter gold mineralization, but with drilling too sparse to include in a Resource. Hole 122 drilled gold mineralization within the intrusion down to a vertical depth of 850m but laterally beyond the previously indicated limits.
Elaine Ellingham, P.Geo., is a Qualified Person (QP) under National Instrument 43-101 and has approved the technical information in this release.
Omai Gold Mines Corp. is focused on expanding the two orogenic gold deposits at its 100%-owned Omai Gold Project in Guyana. In August 2025, the Company announced a 96% increase to the Wenot Gold Deposit NI 43-101 Mineral Resource Estimate to 970,000 ounces of gold (Indicated) averaging 1.46 g/t Au, contained in 20.7 Mt and 3,717,000 ounces of gold (Inferred MRE) averaging 1.82 g/t Au, contained in 63.4 Mt. This brings the global MRE at Omai, including the Wenot and adjacent Gilt Creek deposits, to 2,121,000 ounces of gold (Indicated MRE) averaging 2.07 g/t Au in 31.9 Mt and 4,382,000 ounces of gold (Inferred MRE) averaging 1.95 g/t Au in 69.9 Mt. An updated PEA is planned for H1 2026 to include the expanded Wenot open pit deposit and the adjacent Gilt Creek underground deposit.
Five drills are currently active on the property.
The Omai Gold Mine produced over 3.7 million ounces of gold from 1993 to 2005, ceasing operations when gold was below US$400 per ounce.
For further information, please contact Elaine Ellingham, President & CEO at elaine@omaigoldmines.com or +1.416.473.5351.
Source: Omai Gold Mines Corp.
