black blue board certificate convocation degree di graduation hat mortar Scroll university abstract aged appearance background boards cracked cracks decking flooring grained grains gray grey knots knotting lumber old outdoors outside patterns pier plank planking planks platform rough rustic surface surfaced surfaces surfacing texture textured textures timber viewing-platform wallpaper weathered wood wood-grains wooden brown laquered structure wall attach clips coated color colored colorful colors colour coloured colourful colours contrast drawing-pins fasten golden green hold items mapping-pins notice-board notice-board-pins office office-equipment orange paper-clips pin pink pins red silver sliding clips stationery white yellow alder bark bark felled trees forest fuel stack tree trunks