Marker substances for the coal mining industry were identified as an information and technical reference book to the best available technologies for coal mining and processing. Inorganic dust when emitted into the atmosphere is defined as a marker substance for the coal industry. Inorganic dust emissions belong to the group of fugitive emissions which are carried out from large areas. https://www.lightemupsequences.com/mega-choice-Ball-of-Wisdom-on-sale/