Anthracite iron and nail factory), had determined how to burn anthracite in iron working processing furnaces during the War of 1812, but its use in smelting operations was hit or miss, dependent upon the material packing geometries of any particular charging load in a cold blast furnace. The earlier development of coking of bituminous coal, as well anthracite coke enabled the smelting of iron using local coal sources with cold blast air in blast furnaces after the latter 1830s allowed the production of the vast quantities of iron that built the fundamental infrastructure of the early North American Industrial Revolution — which
Anthracite difficulty of igniting it. This was a particular concern in smelting iron using a blast furnace. With the invention of hot blast in 1828, which used waste heat to preheat combustion air, anthracite became a preferred fuel, accounting for 45% of US pig iron production within 15 years. Anthracite for iron smelting was later displaced by coke. From the late 19th century until the 1950s, anthracite was the most popular fuel for heating homes and other buildings in the northern US, until it was supplanted by oil-burning systems and more recently natural gas systems. Many large public buildings, such as