Methods of working coal seams, which have been given different names in different coalfields, such as stoop-and-room in Scotland; bord-and-pillar in Durham, England; and single and double stalls in South Wales. There are many modifications of pillar mining, but in general, there are two stages: (1) the driving of narrow roadways and thus forming a number of coal pillars, and (2) the extraction of the pillars--often on the retreating 2336 system. Pillar methods of mining are widely used in the United States, while the longwall method is favored in Great Britain. Pillar methods also are used for working stratified deposits of ironstone, rock salt, slate, and other layered minerals.