Summary:
The Nalunaq deposit lies within the Psammite Zone in southern Greenland that hosts the Nanortalik Gold Belt (Hughes et al., 2013). This zone is part of the Ketilidian Mobile Belt which evolved between 1850 Ma and 1725 Ma during interpreted northward subduction of an oceanic plate under the southern margin of the Archean North Atlantic Craton.
Mineralization
The presence of gold mineralisation in south Greenland was first recognised in the early 1990s. Gold occurs in structures both within the supracrustal rocks of the Psammite Zone as well as in the Julianehåb Batholith. The gold is typically associated with arsenic-bismuth-tungsten-copper-(molybdenum). Arsenic is found in small but widespread amounts in the region and is considered a good proxy for gold mineralisation. Mineralisation at Nalunaq, in common with other lode-gold style systems are generally characterised by a high nugget effect (>50%) and the presence of coarse gold particles (>100 µm in size).
Kaltoft et al. (2000) report that the principal mineralised body at Nalunaq, the Main Vein, and associated zones of veining are hosted within a “continuous ductile shear zone” that is related to deformation and metamorphism associated with the regional Nanortalik Nappe structure, emplaced in a brittle-ductile regime during multiple influxes of hypothermal fluids (300–600°C).
Kaltoft et al. (2000) suggest that mineralisation is related to the late-stage deformation events of the Ketilidian Orogeny and were contemporaneous with granite emplacement.
The Main Vein structure varies in width from 0.05 m to 2.00 m, maintains an average dip of 38° towards the southeast, and contains high and sometimes bonanza gold grades (up to 3,777.0 g/t Au over 0.8 m in NQ154, from 92.44 m to 93.24 m). Exposures of the vein in underground development often display pinch and swell structures, show evidence of both compressive and dilatational postmineralisation deformation, and are cut by late aplitic dykes.
The vein also often displays perpendicular quartz-filled tension gashes. These may be developed either upwards from the Main Vein or, more rarely, downwards. Their presence alludes to deformation in a brittle environment, rather than ductile as suggested by previous workers (e.g. Kaltoft et al., 2000).
Gold occurs mostly in the native form and locally as the gold-bismuth alloy maldonite and is associated with native bismuth (Grammatikopoulos et al., 2004). Gold fineness ranges from about 800 to 950. Lollingite and arsenopyrite are also observed. Native gold particles range in size from a few microns up to 8 mm, with coarse visible gold being common in the high-grade sections of the Main Vein.
Vein Complexities
As well as complications caused by offsets on late faults, there are also complexities within the vein itself. Whilst the basic structure that hosts the Main Vein shows continuity over thousands of metres, the vein is more variable and shows marked pinching, swelling and splitting, sometimes reducing from tens of centimetres in width to a few centimetres or pinching-out completely over a few metres. Where the vein pinches out, the hosting structure can still be identified, often with hydrothermal alteration and some minor, poorly mineralised veinlets. In some areas, the Main Vein is cut or invaded by aplite dykes.
Deposit Type
The gold mineralisation at Nalunaq is hosted within an amphibolite-granite sequence and presents characteristics of a narrow-vein orogenic “lode-gold” system.
Commodity Production
Gold production results for 2024 are reported from November 27, 2024, the date of the first gold pour, after a 10-hour processing period.
| Commodity | Units | 2025 | 2024 |
|
Gold
|
koz
| ....  | .... |
All production numbers are expressed as metal in doré.
^ Guidance / Forecast.