Guelb Moghrein is the copper-gold mine just west of Akjoujt, and the reason the town matters beyond its position on the road to Atar. The workings are industrial rather than scenic: open pits, haul roads, dust, and the steady movement of mining vehicles across a hard Saharan plain.
You should not expect a formal tour or casual access. For travellers, the mine is mostly context — a reminder that Mauritania's desert economy is not only camels, dates, and the iron ore railway. If you are passing through Akjoujt, the low hills west of town and the mine traffic give the place its character.