Close but no cigar matey!!
These are the rock cores cut from the bed rock of the Mersey - correct!
They ARE NOT from Lairds jetty tho mate, They are from the legs holding up the jetty`s at Shell, next door!!
Did the re-fit on them couple of years ago, and the cores are at the security gates at shell, Tranmere ( KFC roundabout.), just inside the fence.
Hope this clears things up all!!