Anthracite Mohs scale), its higher relative density of 1.3–1.4, and luster, which is often semi-metallic with a mildly brown reflection. It contains a high percentage of fixed carbon and a low percentage of volatile matter. It is also free from included soft or fibrous notches and does not soil the fingers when rubbed. Anthracitization is the transformation of bituminous coal into anthracite. The moisture content of fresh-mined anthracite generally is less than 15 percent. The heat content of anthracite ranges from 22 to 28 million Btu per short ton (26 to 33 MJ/kg) on a moist, mineral-matter-free basis. The heat content
Anthracite budgerigar mutation Anthracite budgerigar mutation The Anthracite budgerigar mutation is an extremely rare mutation that occurs in the budgerigar. The mutation, similar to the Violet budgerigar mutation, causes a difference in the coloring of budgerigars. Anthracites have black or very dark gray feathers, possibly with some white depending on the budgerigar in particular. The mutation is believed to have started in Germany, and tends to be local to that area. Currently, most owners wishing to obtain an Anthracite need to import these budgerigars from Germany. The description and genetic behaviour of the Anthracite and English Grey are identical, insofar as this can