noun
run-of-the-mine coal; raw coal
Technical term for coal as it comes from the mine, before sorting or processing. Used in mining and energy contexts.
切り込み炭は選別前の石炭で、品質にばらつきがある。
Run-of-the-mine coal is coal before sorting, and its quality varies.
Compound of 切り込み (cutting into, from 切る 'cut' + 込む 'go into') and 炭 (charcoal, coal). The term likely refers to coal that has been cut or extracted from the mine but not yet processed.