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 iron not keep the furnace in operation for more than two months. While distinguished visitors, including Governor Joseph Ritner, acknowledged his success, he sold out his share in Valley Furnace and went to New York City. The research was proceeding along parallel lines across the Atlantic. George Crane, owner, and David Thomas, superintendent of the Yniscedwyn Iron Works, had themselves conceived of the idea of using hot blast to smelt anthracite. Thomas was sent to Scotland to examine Neilson's installation and reproduced it at Yniscedwyn. Crane filed for a British patent on smelting iron with anthracite and hot blast in 1836