In those gentler times I mentioned up thread and since we now seem to be majoring on sticks of rock, I remember coming across a job advert in the Gazette (Blackpool's evening paper).
It was posted by the Coronation Rock Company and read - "Rock, second hand wanted".
I submitted to the Boy's Own Paper and won a copy of the Boy's Own Companion autographed by editor Jack Cox, apparently now rare and valuable -
https://www.worldofbooks.com/en-gb/...CjZ0bO3PLNetmRMlbAemlKdMZQnX0-vRoC9LsQAvD_BwE
and since this is a hifi forum, available at a discount if you buy it with vinyl!
I remember Coronation had an 'outlet shop' at the factory selling miss shapes and bags of broken rock. Judging by the variety of seaside resorts represented Blackpool was the centre of the rock industry
Jim