material for the landform

That is the roof destroyed by Katrina. When I saw these pictures a cool idea came to me!  I do not want grass covered the landform , I would use the material that is for the real roof to cover the landform and keep the cool shape. Or at least I would use the color of the real roofing material. What is the material for roof in New Orleans? I searched something… and.. metal.. tile..fiber cement.. who knows…

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