1 Correction to: Int J Coal Sci Technol https://doi.org/10.1007/s40789-020-00369-2

In the original publication the resolution of Figures 1 and 2 need improvement. The correct version of figures is available in this correction. The original article has been corrected.

Fig. 1
figure 1

Intensely crushed core from the floor of the work site

Fig. 2
figure 2

Entirely crushed core from the floor of the work site