Anthracite iron charcoal — long the fuel of preference for smelting and glass making, creating a decades long search for alternative fuels. By mid-1792 prominent Philadelphians had formed the Lehigh Coal Mine Company (LHCM Co.) to bring Anthracite to cities reachable via the Delaware River Valley, especially Philadelphia — the nation's largest and most industrialized city, though no one fully understood how to use anthracite as a sole fuel—just that "it 'could' burn 'some' of the time" with a hot enough base fire, so could augment furnace fuels. The LHCM Co. had great difficulty getting many ark-loads of coal to the docks
Anthracite budgerigar mutation the Anthracite locus. This darkens the body colour to a shade somewhat deeper than a Dark Green. The DF Anthracite Light Green, with two Anthracite alleles, is a deep olive colour. In the blue series varieties the SF Anthracite Skyblue has one Anthracite allele and one wild-type allele, with a body colour rather like a deep Cobalt. The DF Anthracite Skyblue with two Anthracite alleles, the true Anthracite variety, has a dark grey, almost black, body colour with mauve overtones. Because the Anthracite factor is always visibly expressed no budgerigar can be split for Anthracite. The heterozygotes of Anthracite with