There are numerous cachets identified with the Moroccan stamps on it.
The official issuing date is 19 April, however, the FD cancellation is dated the day after, on 20 April 1958. There are 2 different cancellation known of that day: the official 'premier jour' (First Day) of Casablanca and on the same day, you can find covers cancelled in Tetuan. The cancellation either depicts an hour or * at the place of hour. Some covers are cancelled even the day after in Tanger or during the period till the end of the Brussels Exhibition happening.
The order of the first day covers below are of no importance or rarety:
FDC Cover Cassablanca 20 April 1958
FDC Cover Tetuan 20 April 1958
With no indication of hour on the cancellation
With indication of hour on the cancellation(same design as the previous one but with other issued colours)
Two same design but clear differences like the star emblem, font width, height
FDC Cover Tanger 21 April 1958
Other covers cancelled on other day:
Combo FDC Cover Cassablanca 20 April 1958 (other cancellation more than 1 month later):
