History of anthracite coal mining in Pennsylvania railroad system made transporting the anthracite exponentially easier, and by the 1860s anthracite coal was regularly supplying urban centers like Philadelphia and New York City and was helping to fuel the American Industrial Revolution. Anthracite and bituminous coal were formed in the eastern and western regions of Pennsylvania respectively during the Pennsylvanian time in the Carboniferous Geological Period (“History of Anthracite Coal Mining”). The Pennsylvania Anthracite Region is in the Valley and Ridge Province of the Appalachian Mountains, with the coal located in the folded and faulted terrain of the Province. The anthracite fields are maintained in synclinal basins that
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