Blue Ground is a first-person diamond-mining game set on the red plateau of South Africa’s Northern Cape, near Kimberley. You inherit Grete’s old concession: a dusty kopje, a 1914 headframe and a shaft nobody has opened for a century. Somewhere in the blue ground below — the old miners’ name for the diamond-bearing kimberlite — lie five legendary diamonds.

Start with your hands. Scoop red earth with a trowel, carry it in a bucket, wash it in the hand sieve and sell your first tiny stone at the exchange. Buy a shovel, a wheelbarrow, a pickaxe and a jackhammer, and dig down through red earth, calcrete, shale, a coal seam, the yellow ground and finally the blue kimberlite. Every column you dig is real: walls slump, rubble piles up, water rises below −15 m and must be pumped out.

Then build a mine. Research more than 50 machines and automate everything: excavator arms and bucket wheels feeding belts, grizzly screens, jaw and cone crushers, a blue rotary scrubber, trommels, a heavy-media separator, X-ray sorters, the grease table and the glovebox where you sort the stones yourself. Wire it with diesel gensets, solar panels or a coal steam engine. Pipe water from the tower. Drill, charge and blast the hard dolerite, take core samples to find the rich ground, and restore Grete’s old cableway.

Hunt the legends. The Kopje Star, the Widow’s Tear, the Blue Duchess, Ironheart and the Heart of the Pipe are buried at real depths in the pipe. Find all five and display them in the vault.