Lutsk – returned tombstones at the massgrave site
Lutsk – returned tombstones at the massgrave site
Lutsk – returned tombstones at the massgrave site
Vanished World
"The traces were still there. But time would slowly blur them and nothing would be left." – Edgar Hilsenrath
Vanished World 
That round “returned tombstone” was cut or chipped or carved into round and turned into a grinding stone. Look at that depression in the center: it’s marks the axis, and locates the grinding stone.