I just visited Omaha beach and was looking to find something. The beach only had seashells, dead crabs and seaweed. I randomly found one piece of coal. There were no other rocks anywhere to be found. Is there a chance this is a remanent or D day? Did the boats use coal? The coal was pretty solidified so imagine it’s pretty old.
Thanks!
Without detailed chemical analysis, and often not then, it is impossible to tell where a particular piece of coal is from.
Coal is frequently found on beaches in north east England from outcropping under the sea that are eroding, indeed picking it off beaches was an early way of gathering it. So given North Sea currents it could have come there.
There are very small sea outcroppings in the Kent coalfields on the south east coast of England.
There are significant coal measures in the Pas de Calais ( although I am not aware of any that are on the coast) and some very small measures in Normandy.
It could also have been part of a cargo lost in what is one of the worlds busiest shipping passages.