Anthracite burns with a short, blue, and smokeless flame. Anthracite is categorized into standard grade, which is used mainly in power generation, and high grade (HG) and ultra high grade (UHG), the principal uses of which are in the metallurgy sector. Anthracite accounts for about 1% of global coal reserves, and is mined in only a few countries around the world. China accounts for the majority of global production; other producers are Russia, Ukraine, North Korea, South Africa, Vietnam, the UK, Australia, Canada and the US. Total production in 2010 was 670 million tons. Anthracite derives from the Greek "anthrakítēs" (),
What is a Masterpiece? confluence of memories and emotions forming a single idea", that it has "a power of recreating traditional forms so that they become expressive of an artist's own epoch and yet keep a relationship to the past". The highest masterpieces are said to be "illustrations of great themes." Clark also implicitly excluded the erotic from considerations of what constituted a masterpiece, based on his perspective that a necessary condition is the balance between sense and form (works that are too sensual are, therefore, unbalanced and not to be categorised at masterpiece level). What is a Masterpiece? What is a Masterpiece? is