I find small rocks in all brands of lump that I have tried. It doesn't bother me as I know the process. I prefer a couple of stones to raw bark that just flames and is gone. At least the rocks (pebbles really) retain heat.
Backyard Disasters are my specialty.
"Tushka" The Black Warrior 24 x 50 offset by TuscaloosaQ, "Libby the Lion" L5000 gasser, and "Vanessa" my Vision Kamado Pro III & "Ruprecht" my Weber Gold OTG
Member KCBS, FBA
Pitmaster at "Sultans of Sting" BBQ Team it's a French thing!