Anthracite dust, the grey of a mine after the black coal has been hauled out.
Hard Coal is a neutral grey.
It can be described as neutral, medium and colorless.
Set in white, because white reads best on it.
Anthracite, also known as hard coal and black coal, is a hard, compact variety of coal that has a submetallic lustre. It has the highest carbon content, the fewest impurities, and the highest energy density of all types of coal and is the highest ranking of coals.
Read on WikipediaCoal is a combustible black or brownish-black sedimentary rock, formed as layers called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. It is a fossil fuel, formed when plants decay into peat which is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits formed from wetlands called coal forests that covered much of the tropics during the late Carboniferous and early Permian.
Read on WikipediaNoun