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 budgerigar mutation now be determined. It seems likely that the Anthracite is the re-emergence of the English Grey. A bird with two Anthracite factors has an extremely dark grey body, jet black markings and the cheek patches of the same very dark grey as the body. G W von Kamrath describes them as "jet black wing and tail markings and deep black cheek patches". A single Anthracite factor has a similar effect to the Dark mutation, causing a Skyblue to become Cobalt in appearance. The Anthracite mutation appeared in Germany in 1998 in the aviaries of Hans-Jürgen H Lenk, who successfully established