Anthracite latter in two or three sizes, all three being above in (38 mm) size on round-hole screens. High grade (HG) and ultra high grade (UHG) anthracite are the highest grades of anthracite coal. They are the purest forms of coal, having the highest degree of coalification, the highest carbon count and energy content and the fewest impurities (moisture, ash and volatiles). High grade and ultra high grade anthracite are harder than standard grade anthracite, and have a higher relative density. An example of a chemical formula for high-grade anthracite would be CHONS, representing 94% carbon. UHG anthracite typically has a
Coal mining in the United Kingdom or low-carbon sources and loss of industry due to globalisation. Oil and gas reserves are predicted to run out long before coal, so gas could be produced from coal by gasification. On 21 April 2017, Britain went a full day without using coal power to generate electricity for the first time since the Industrial Revolution, according to the National Grid. In April 2018, a new record was set of 55 hours without coal, which in turn was broken by a period of more than 72 hours without coal a few days later. Coal mining in the United Kingdom Coal mining