one of the things about living down river from London is that this area has been used as a dump for the capitals waste for centuries. On one of my wider ranging cycles routes (when I have the energy to get up early on a Sunday morning) is a rubbish land fill site slowly washing out into the river. I don't know exactly how old it is but around 1900's would be my guess
this was made with a piece of copper pipe found in the road, I really like the texture you get from a piece of metal that has been run over hundreds of times, I have tried to reproduce it with "virgin" copper but never succeeded