Ключевые слова: black, cave, cavern, coal, copper, dark, deposit, dirt, drift, electric, gallery, geology, gold, heavy, industrial, industry, iron, locomotive, machine, metal, mine, miner, mineral, mining, old, ore, passage, quarry, rail, railroad, railway, rock, shaft, steel, stone, technology, track, train, transport, transportation, tunnel, underground, vehicle, vintage, wagon,