For some years I have been given a type of shingle...

For some years I have been given a type of shingles that have proved to be fragile and with an antiqued surface but which has lost its maculated appearance and has become dark in color; this is more evident in the water table in the north but is also present in the other. In the particular photo of the roof it is evident how the part placed under the door appears intact while the exposed one has lost its characteristic maculata and shaded.