how to create a partition in free space using GNU Parted

Number  Start   End     Size    File system
    ......................................
        468GB   520GB   52.4GB  Free Space

Well, as you can see Start is 468GB and End is 520GB. Now, parted defaults to MB so you'll have to specify the unit:

unit GB mkpart primary ntfs 468 520

or append unit suffix to the start/end numbers:

mkpart primary ext2 468GB 520GB

Alternatively, you can list the values in MB with

unit MB print free

and then use the start/end values without any unit/suffix e.g.

mkpart primary ext2 468012 520008

Another solution would be to use percentage unit (%) to specify sizes:

 sudo parted -s /dev/sdX mkpart primary 0% 100%

If a label is not present in the disk device, you will need to create it first. For example:

 sudo parted -s /dev/sdX mklabel msdos

Caution! 0% and 100% points correspondingly to the start and to the end of entire physical disk, and not just free space. So if you run sudo parted -s /dev/sdX mkpart primary 0% 100%, this will destroy all existing partitions.