Regional exploration last year on its Indin Lake property, 200 km north of Yellowknife in the Northwest Territories turned up high-grade gold in grab samples taken in three different areas including 174.50 grams gold per tonne at Fishhook, the southernmost project on its 899-sq-km land package, Nighthawk Gold (TSX: NHK; US-OTC: MIMZF) reports.
Fishhook consists of several historical gold showings spanning an area of 6 km by 1.5 km, 40 km southwest of the company’s main Colomac project. Grab samples from the 2018 exploration program at Fishhook returned 15.30 grams gold per tonne, 9.88 grams gold, 7.94 grams gold and 5.83 grams gold.
The showings at Fishhook are hosted by complex folded amphibolitic oxide-silicate iron formation within a sequence of metasedimentary rocks—an environment Nighthawk says is similar to its Damoti Lake gold deposit, 28 km south of Colomac.
Last June, Nighthawk updated the resource for its flagship Colomac project to 50.3 million inferred tonnes grading 1.62 grams gold per tonne for 2.6 million ounces of contained gold. The resource includes three gold deposits: Colomac, Grizzly Bear and Goldcrest.
The Colomac main deposit was mined intermittently from 1990 to 1997 with reported production of 527,908 ounces of gold with an average head grade of 1.66 grams per tonne.
Exploration last year also found new areas of high-grade mineralization within the Nice Lake Sill, where grab samples returned 41.90 grams gold, 38.90 grams gold and 19.05 grams gold.
The Nice Lake Sill was discovered in 2016 while Nighthawk was prospecting a large linear anomaly 1.5 km to the east of Colomac that displayed similarities in magnetic intensity and anomaly shape to both the Colomac and Goldcrest sills. The Nice Lake sill has been traced for over 4 km in outcrop along a trend sub-parallel to the Colomac sill.
Outcrop mapping between Colomac, Nice Lake and areas to the east of Nice Lake, also identified multiple smaller sills within a 2-km-wide corridor and the company believes that the sills show the same intensity of deformation and alteration as that found in association with gold within the Colomac main sill.
The company also found a new area of high-grade gold mineralization at Andy Lake, 20 km south of Colomac, where a grab sample from last year’s program returned 42.10 grams gold. Other notable samples included 8.79 grams gold and 3.46 grams gold. Nighthawk believes Andy Lake has the potential for hosting an intrusion-related gold system dominated by mineralized quartz veins.
At Laurie Lake, 8.5 km northwest of Colomac, surface samples taken from a 1.3 km by 1.7 km area returned values ranging from 1.05 grams gold to 22.50 grams gold. The 2018 prospecting program at Laurie Lake was a follow-up of Nighthawk’s work there in 2014, when it sampled gold-bearing sulphide mineralization within the Laurie Lake iron formation. At that time, 44 samples were analyzed with 38 containing gold at or above detection limits with the best sampled from an oxidized foliated banded iron formation assaying 4.17 grams gold.
Sampling of a historic trench at Treasure Island, meanwhile, which sits 11 km to the north of Colomac and about 4 km from Laurie Lake, returned up to 45.60 grams gold.
Treasure Island is the northernmost project on the Indin Lake property and lies within the eastern end of the 7-km-long Treasure Island-Laurie Lake mineralized corridor, which contains several surface gold showings.
The company first drilled Treasure Island in 2011 to test the main zone along the southern edge of the island and all of the holes reported gold mineralization. The company drilled 16 holes last year in a 4,035-metre program and all of them intersected mineralization, with visible gold in 14 of them.
Highlights included 46.3 metres grading 3.31 grams gold from 118 metres downhole, including 21.8 metres of 6.23 grams gold, and 18.5 metres grading 7.37 grams gold from 165 metres below surface, including 8 metres of 16.14 grams gold.
So far, drilling at Treasure Island has confirmed the gold system is upwards of 200 metres wide, 700 metres long, and open in all directions. The company believes Treasure Island could become a high-grade feeder to any future mining scenario at Colomac.
Nighthawk also completed the first-ever drill holes on its Swamp project, 6 km northwest of Colomac. The best results were 6.83 grams gold over 0.65 metre from 111.85 metres below surface and 3.33 grams gold over 3.25 metres from 116.50 metres downhole, including 6.06 grams over 0.75 metre. Nighthawk says it needs more work to fully evaluate Swamp’s 1.6 km by 1 km mineralized footprint.
Other exciting regional targets on the property are Leta Arm, 15 km southwest of Colomac, and Damoti Lake.
Leta Arm straddles the Leta Arm fault zone, a north- to south-trending regional deformation zone up to 10 km long and 500 metres wide, which hosts two historical gold mines—North Inca and Diversified—and two gold showings, No. 3 and Lexindrin.
The Diversified mine is 1.3 km north of the North Inca mine and the No. 3 showing is situated in between the two (450 metres south of the Diversified shaft and 800 metres south of North Inca’s East zone. Lexindrin is 1.2 km north of the Diversified shaft.
Damoti Lake is a deposit in iron formation. Previous owners, Anaconda Gold, completed a resource estimate in 2005 outlining 40,600 measured and indicated tonnes grading 26.17 grams gold in addition to 17,800 inferred tonnes grading 16.38 grams gold at an 8 gram cut-off grade.
Nighthawk estimates its Indin Lake property takes up 95% of the Indin Lake greenstone belt—roughly three times the size of the core Timmins camp, by its estimates.
According to its most recent corporate presentation, Northfield Capital Corporation owns a 15% stake in the company, Kinross Gold Corp. (TSX: K; NYSE: KGC) owns 9%, Osisko Gold Royalties (TSX: OR) 9%, and institutional investors 19%.
This story first appeared in The Northern Miner.