This is the cephalon of a Harpes sp. trilobite from the Middle Hamar Laghdad Limestone near Tafilalt, Morocco. It's only a partial but displays the prominent flattened margins around the cephalon. I purchased it from Geological Enterprises as a reference piece of what a non faked Moroccan trilobite can look like. The specimen is not perfect with part of the glabella ground off but otherwise there is little restoration.
Based on the web site Paleodb.org the Middle Hamar Laghdad Limestone is lower Devonian (upper Emsian) in age