We live in Ireland. When we are in Dublin, we burn smokeless fuel to prevent air pollution.* However, at the mother-in-law’s house beyond the Pale, the coal supplied is ordinary coal from Poland.
Occasionally I find a small piece of wood in the coal. When I was young, I believe most coal sold in ireland came from the UK. Even then, I remember sometimes seeing a small piece of wood in coal.
The wood is a tiny percentage of the volume, so no one is trying to cheat us by diluting coal with wood. As coal is sold by weight not volume, it would not make much sense to try that. In any event it is a very small volume, and seems like an impurity which finds its way into coal.
This wood is the only impurity that I see in the coal. Otherwise, it is pure chunks of carbon as mined from the ground - no bits of plastic or stones or pieces of miner.
Where does this wood come from? is it pulled in during the mining process? Surely they don’t use wooden props in mining today?
Or does it fall in somewhere in the transport process from the Polish mine to me?
*I remember the choking fogs of Dublin’s past, and I still offer thanks to Mary Harney for her courage in forcing through clean air in the face of vicious opposition from vested interests. A lady with guts, who got shafted by the vested interests in the Health Service. But that’s a different question.