Older roof covering type?

Saw this roof covering on an older, 1928 house, today. Was not slate, although looked that way. Was some sort of fiberous composite. No real breakage or missing pieces. Some aglae accumulation. All gutters and flashing were the original copper and there was open copper valleys.

Anyone know the specific type?



It looks like asbestos from here. (about 350 miles)

BOY, you got good eyes! :mrgreen:

Possibly a resin type shingle Will??? I’ve heard of this type installed in hail prone areas. i.e. tuff to withstand damage.