Enter the Petromax Aramid Pro 300 gloves! We tested these whilst cooking on briquettes and wood and used them to move the coals around by hand and also to move the grill on and off the barbeque. They were surprisingly comfortable to use and protect not only your hands but also your forearms, so you don't experience that burnt hair smell when adjusting the coals.
Very little heat got through the gloves in normal use, even when moving the hot coals and logs around.
These gloves do not make you invincible to longer periods of heat. We held on to a coal for longer than was necessary and found that longer exposure to such severe heat did result in more heat coming through the gloves to the point where it was uncomfortable after several seconds. They would not be used in this way in normal use, this was just for testing purposes.
However, as I say above, for normal use these gloves were great and offered a really good level of protection! There were no signs of burn marks on the gloves and they are exceptionally well made and robust.