Thomassen reported in 2003 that the Black Angel mine took its name from a pelite outcrop that forms a dark angel-like figure on a precipitous cliff face of marble above Affarlikassaa fjord. The mineralized zone actually crops out just above the angel figure about 700 m above fjord level. The 1100 m high Angel mountain is situated at the margin of the Greenland ice cap at 71°N lat. on the west coast of Greenland, about 500 km north of the Arctic Circle, where there is two months of winter darkness.
The peninsula across the fjord housed the mining camp, concentrator and all services and received its name Maarmorilik from a former marble quarry situated there from the 1930s. The only access to the mine from these facilities was by two aerial tramways. The Black Angel deposit comprised ten ore bodies totaling 13.6 million tons grading 12.3% Zn, 4.0% Pb and 29 ppm Ag. Of these 11.2 million tons were extracted in the period 1973–90. The mining operations ceased when the extractable ore reserves were exhausted, leaving 2.4 million tons of ore tied up in pillars and other areas inaccessible to mining.
Carbonate-hosted lead-zinc mineralization is common in the Mârmorilik Formation and in the mine area stratabound sulfide mineralization occurs at various levels. The main ore bodies are located 600–700 m a.s.l. in the upper part of the sequence, which is dominated by calcitic marble, whereas the satellite ores of Nunngarut to the south are hosted in the lower part of the sequence dominated by dolomite marble. The distribution of ore bodies is controlled by a major z-fold with a 070°-striking near-horizontal axis. The ore forms flat-lying, highly deformed, massive lenses
up to 30 m thick, of which ten reach economic size and were mined.
The massive ore consists of pyrite, sphalerite and galena, with abundant rotated marble fragments and quartz inclusions. The main accessory ore minerals are pyrrhotite, chalcopyrite, tennantite and arsenopyrite. Cherty horizons and disseminated graphite are quite common in the wall rocks whereas minor fluorite and baryte are restricted to a few of the ore bodies. Various ore tectonites have been distinguished – massive ore, banded ore, porphyroclastic ore or "buck shot ore" and remobilized ore.
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