Crushing run-of-mine coal alters the proportion of particles in a given density class because of the coal's naturally occurring diversity in particle size and specific gravity. Because of this, the gravity-based coal washing process loses some of its effectiveness in terms of producing clean coal and maintaining high quality coal during the separation phase. The amount of 'near-gravity material' (material with a specific gravity within the range of 0.1) present in a normal coal at a given specific gravity makes washing the coal more challenging. Here, we employ two numerical indices—the 'near-gravity material index' and the 'index of washability'—to quantify the distribution of near-gravity material across density classes and to assess the degree of difficulty involved in the washing process. In order to remain competitive in the global coal market, India's coal businesses rely heavily on the process of beneficiating lower-grade coal, which presents significant obstacles.