Coal breaker remaining. The sorting by size is particularly important for anthracite coal. In order to burn efficiently, air must flow evenly around anthracite. Subsequently, most anthracite coal is sold in uniform sizes. In the 1910s, there were six commercial sizes of coal (with the smallest size having three subsets): Coal pieces smaller than in size were considered "culm," and unable to be separated from the impurities (and thus useless). The grade of coal ranged from a low of 5 percent impurities for steam or broken coal to a high of 15 percent for pea-size coal and its subsets. Coal breakers were
World Figure Skating Championships cumulative medal count World Figure Skating Championships cumulative medal count The following is the "cumulative medal count" for countries at the World Figure Skating Championships. It includes countries that no longer exist. Boldface denotes active skaters and highest medal count among all skaters (including these who not included in these tables) per type. Boldface denotes active skaters and highest medal count among all skaters (including these who not included in these tables) per type. Boldface denotes active skaters and highest medal count among all pairs or separate partners (including these who not included in these tables) per type. Italic denotes statistics of performances