Anthracite mined on the generally flat lying and undeformed sedimentary rocks further west on the Allegheny Plateau of Kentucky and West Virginia, Eastern Ohio, and Western Pennsylvania. In the same way the anthracite region of South Wales is confined to the contorted portion west of Swansea and Llanelli, the central and eastern portions producing steam coal, coking coal and domestic house coals. Structurally, anthracite shows some alteration by the development of secondary divisional planes and fissures so that the original stratification lines are not always easily seen. The thermal conductivity is also higher; a lump of anthracite feels perceptibly colder when
Anthracite budgerigar mutation just one Anthracite allele correspond to the splits of recessive mutations. A single Anthracite factor has a similar effect to the Dark mutation, causing a Skyblue to become Cobalt in appearance - as was suspected with the English Grey. In fact, the similarity of the Anthracite to the English Grey is striking. The description is virtually identical, and the cobalt appearance of a Skyblue with a single Anthracite factor is exactly what was suspected for the English Grey. The interaction of the Anthracite and Dark budgerigar mutations has not yet been investigated. It is expected that a combination of the