Yes and no, not with a magnet, since it was all mostly filled with dirt, and the magnet will not attach to aluminium. But I did find some pieces when I started moving the rocks.
Looking for militaria from 38. Batterie, Heeres Küsten Artillerie Regiment 977, also from 31, 32 and 36. Batterie.
I tested a bit my magnet and for me it was a turndown. Not the magnet itself but it has very few applications over here: Sea - the places where stuff have been dumped after WW2 are very rocky and the chance of having it stuck there is higher than you grab something nice. Moreover there is the high chance you may grab something not funny. Lake - no clean lakes to try. If there is something good, is buried under industrial garbage thrown there in the 50's. Wells - mostly I searched were dry and filled with garbage, no luck at all.
I have few spots to try but my suggestion is to find the good spots BEFORE buying it
Together with me and a few friends have been going every year for meetings and we fish magnets lakes and rivers. The fact is that most often the things learned from the water belong to these dangerous as seen in my Avatar,. However, there are some really interesting findings. Below I present some pictures.
Truly agree with Inf Div 121 magnets only work good in a neat n clean water. water should be without pollution and crappy material and for detecting you also should have a heavy powerful magnet. i use this magnet which i got from my broken heavy speakers