In 1876 Alfred Caillard Pasha succeeded Giacomo Muzzi as Director General of Posts, changing the Post Office's secondary language from Italian to French. Caillard awarded the contract for a new set of stamps to De La Rue of London, with notable changes in the quality of the design, paper, printing and perforation. The designs had different frames in order to distinguish the various values, the sheets were of 240 stamps instead of the previous 200-stamp sheets, because the sheet size was in accord with the British monetary system to which of De La Rue's machinery was adapted. This fourth issue was to have a run of 34 years with changes in denominations, colours and currency type.
The 4 millièmes (1906) is the only Fourth issue stamp found only on chalky paper.
Others reprinted are 1, 2, 3 (not the maroon), 5 millièmes, 1, 2, 5 and 10 piastres.