I block copied a 50 GB linux partition (almost full, 92% used), from a disk which had started to have some errors to a 666 GB partition of a 750 new hard drive using   ddrescue -v -d -r 3 -f /dev/... /dev/... After using grub I was able to boot from the new hard drive  without any noticeable problems.While I somehow expected that I might need to resize the result of my copying, now both gparted and df report that my new drive is close to being full, however in different ways: gparted says that 660 GB  have been used out of 666 GB available in the partition, and  df claims the partition has 41 GB in use out of a total of 47 GB.I don't understand what is wrong, nor how to interpret the vastly different sizes of /dev/sda1/by gparted and df. I am lost and would appreciate suggestions about how one can recover the use of the space in the new disk  which I expected to be more than 90% free, even after putting the contents of the old.
gparted, df and resizing a hard drive partition
disk usage;gparted